The U-boat Campaign from 1914 to 1918 was the
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
naval
A navy, naval force, or maritime force is the branch of a nation's armed forces principally designated for naval warfare, naval and amphibious warfare; namely, lake-borne, riverine, littoral zone, littoral, or ocean-borne combat operations and ...
campaign fought by German
U-boat
U-boats were naval submarines operated by Germany, particularly in the First and Second World Wars. Although at times they were efficient fleet weapons against enemy naval warships, they were most effectively used in an economic warfare role ...
s against the trade routes of the
Allies
An alliance is a relationship among people, groups, or states that have joined together for mutual benefit or to achieve some common purpose, whether or not explicit agreement has been worked out among them. Members of an alliance are called ...
. It took place largely in the seas around the
British Isles
The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, ...
and in the
Mediterranean
The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the e ...
.
The
German Empire
The German Empire (),Herbert Tuttle wrote in September 1881 that the term "Reich" does not literally connote an empire as has been commonly assumed by English-speaking people. The term literally denotes an empire – particularly a hereditary ...
relied on imports for food and domestic food production (especially fertilizer) and the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...
relied heavily on imports to feed its population, and both required raw materials to supply their war industry; the powers aimed, therefore, to
blockade
A blockade is the act of actively preventing a country or region from receiving or sending out food, supplies, weapons, or communications, and sometimes people, by military force.
A blockade differs from an embargo or sanction, which are le ...
one another. The British had the
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against F ...
which was superior in numbers and could operate on most of the world's oceans because of the
British Empire
The British Empire was composed of the dominions, colonies, protectorates, mandates, and other territories ruled or administered by the United Kingdom and its predecessor states. It began with the overseas possessions and trading posts esta ...
, whereas the
Imperial German Navy
The Imperial German Navy or the Imperial Navy () was the navy of the German Empire, which existed between 1871 and 1919. It grew out of the small Prussian Navy (from 1867 the North German Federal Navy), which was mainly for coast defence. Wilhel ...
surface fleet was mainly restricted to the
German Bight
The German Bight (german: Deutsche Bucht; da, tyske bugt; nl, Duitse bocht; fry, Dútske bocht; ; sometimes also the German Bay) is the southeastern bight of the North Sea bounded by the Netherlands and Germany to the south, and Denmark and ...
, and used
commerce raiders
Commerce raiding (french: guerre de course, "war of the chase"; german: Handelskrieg, "trade war") is a form of naval warfare used to destroy or disrupt logistics of the enemy on the open sea by attacking its merchant shipping, rather than enga ...
and
unrestricted submarine warfare
Unrestricted submarine warfare is a type of naval warfare in which submarines sink merchant ships such as freighters and tankers without warning, as opposed to attacks per prize rules (also known as "cruiser rules") that call for warships to sea ...
to operate elsewhere.
In the course of events in the Atlantic alone, German U-boats sank almost 5,000 ships with nearly 13 million
gross register tonnage, losing 178 boats and about 5,000 men in combat.
Other naval theatres saw U-boats operating in both the Far East and South East Asia, the Indian Ocean and the Mediterranean and North Seas.
1914: Initial campaign
North Sea: Initial stage
![Submarine U-14 (LOC) (6358166395)](https://upload.wikimedia.org/wikipedia/commons/9/97/Submarine_U-14_LOC_6358166395.jpg)
In August 1914, a flotilla of ten U-boats sailed from their base in
Heligoland
Heligoland (; german: Helgoland, ; Heligolandic Frisian: , , Mooring Frisian: , da, Helgoland) is a small archipelago in the North Sea. A part of the German state of Schleswig-Holstein since 1890, the islands were historically possessions ...
to attack
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against F ...
warships in the
North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...
in the first submarine war patrol in history. Their aim was to sink capital ships of the British Grand Fleet, and so to reduce the Grand Fleet's numerical superiority over the German High Seas Fleet. The first sortie was not a success. One of
''U-9'''s engines broke down and she had to return to Heligoland. Only one attack was carried out, when fired a torpedo (which missed) at . Two of the ten U-boats were lost.
Later in the month, the U-boats achieved success, when sank the cruiser . In September,
sank three armoured cruisers (, , and ) in a single action. Other successes followed. In October ''U-9'' sank the cruiser and ''U-27'' sank the submarine
''E3'', the first time one submarine sank another, and on the last day of the year sank the
pre-dreadnought
Pre-dreadnought battleships were sea-going battleships built between the mid- to late- 1880s and 1905, before the launch of in 1906. The pre-dreadnought ships replaced the ironclad battleships of the 1870s and 1880s. Built from steel, prote ...
battleship . By the end of the initial campaign, the U-boats had sunk nine warships while losing five of their own number.
[Tarrant p10, 11]
Mediterranean: Initial stage
The initial phase of the U-boat campaign in the Mediterranean comprised the actions by the
Austro-Hungarian Navy
The Austro-Hungarian Navy or Imperial and Royal War Navy (german: kaiserliche und königliche Kriegsmarine, in short ''k.u.k. Kriegsmarine'', hu, Császári és Királyi Haditengerészet) was the naval force of Austria-Hungary. Ships of the A ...
's U-boat force against the French, who were blockading the
Straits of Otranto. At the start of hostilities, the Austro-Hungarian Navy had seven U-boats in commission; five operational, two training; all were of the coastal type, with limited range and endurance, suitable for operation in the Adriatic. However during the war new larger U-boats came into service plus Germany shipped several overland. The Austro-Hungarian U-boats had a number of successes. On 21 December 1914 torpedoed the (beyond Otranto), causing her to retire to Malta for serious repairs, and on 27 April 1915 sank the , with a heavy loss of life.
Submarine warfare
In 1914 the U-boat's chief advantage was to submerge; surface ships had no means to detect a submarine underwater, and no means to attack even if they could, while in the
torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, su ...
the U-boat had a weapon that could sink an armoured warship with one shot. Its disadvantages were less obvious, but became apparent during the campaign. While submerged, the U-boat was virtually blind and immobile; boats of this era had limited underwater speed and endurance, and so needed to be in position before an attack took place, while even on the surface their speed (around 15 knots) was less than the cruising speed of most warships and two-thirds that of the most modern dreadnoughts.
The U-boats scored a number of impressive successes, and were able to drive the
Grand Fleet
The Grand Fleet was the main battlefleet of the Royal Navy during the First World War. It was established in August 1914 and disbanded in April 1919. Its main base was Scapa Flow in the Orkney Islands.
History
Formed in August 1914 from the ...
from its base in search of a safe anchorage, but the German Navy was unable to erode the Grand Fleet's advantage as hoped. Also, in the two main surface actions of this period the U-boat was unable to have any effect; the
High Seas Fleet
The High Seas Fleet (''Hochseeflotte'') was the battle fleet of the German Imperial Navy and saw action during the First World War. The formation was created in February 1907, when the Home Fleet (''Heimatflotte'') was renamed as the High Seas ...
was unable to draw the Grand Fleet into a U-boat trap. Whilst warships were travelling at speed and on an erratic
zigzag
A zigzag is a pattern made up of small corners at variable angles, though constant within the zigzag, tracing a path between two parallel lines; it can be described as both jagged and fairly regular.
In geometry, this pattern is described as a ...
course they were relatively safe, and for the remainder of the war the U-boats were unable to mount a successful attack on a warship travelling in this manner .
First attacks on merchant ships
The first attacks on merchant ships had started in October 1914. At that time there was no plan for a concerted U-boat offensive against Allied trade. It was recognised the U-boat had several drawbacks as a commerce raider, and such a campaign risked alienating neutral opinion. In the six months to the opening of the commerce war in February 1915, U-boats had sunk 19 ships, totalling .
1915: War on commerce
Unrestricted submarine warfare
![Map of ships sunk in WWI 1915](https://upload.wikimedia.org/wikipedia/commons/c/c0/Map_of_ships_sunk_in_WWI_1915.jpg)
By early 1915, all the combatants had lost the illusion that the war could be won quickly, and began to consider harsher measures in order to gain an advantage.
The British, with their overwhelming sea power, had established a naval blockade of Germany immediately on the outbreak of war in August 1914, and in early November 1914 declared it to be a war zone, with any ships entering the North Sea doing so at their own risk. The blockade was unusually restrictive in that even food was considered "contraband of war". The Germans regarded this as a blatant attempt to starve the German people into submission and wanted to retaliate in kind, and in fact the severity of the British blockade did not go over well in America either.
Germany could not possibly deal with British naval strength on an even basis, and the only possible way Germany could impose a blockade on Britain was through the U-boat. The German Chancellor,
Theobald von Bethmann Hollweg
Theobald Theodor Friedrich Alfred von Bethmann Hollweg (29 November 1856 – 1 January 1921) was a German politician who was the chancellor of the German Empire from 1909 to 1917. He oversaw the German entry into World War I. According to biog ...
, felt that such a submarine blockade, based on "shoot without warning", would antagonise the United States and other neutrals. However, he was unable to hold back the pressures for taking such a step.
In response to the British declaration in November 1914 that the entire North Sea was now a war zone, on 4 February 1915 Admiral
Hugo von Pohl
Hugo von Pohl (25 August 1855 – 23 February 1916) was a German admiral who served during the First World War. He joined the Navy in 1872 and served in various capacities, including with the new torpedo boats in the 1880s, and in the ''Reic ...
, commander of the German High Seas Fleet, published a warning in the ''Deutscher Reichsanzeiger'' (Imperial German Gazette):
In time, this would bring non-European nations (such as Brazil and the United States) into the war.
The German U-boat force was now primarily based at
Ostend
Ostend ( nl, Oostende, ; french: link=no, Ostende ; german: link=no, Ostende ; vls, Ostende) is a coastal city and municipality, located in the province of West Flanders in the Flemish Region of Belgium. It comprises the boroughs of Mariakerk ...
in Belgium, giving the submarines better access to the sea lanes around England. The Germans made use of this advantage, sending out about 20 U-boats to begin the naval blockade. In January, before the declaration of "unrestricted submarine warfare" as the submarine blockade was called, 43,550 tonnes of shipping had been sunk by U-boats. The number of sinkings then steadily increased, with 168,200 tonnes going down in August. Attacking without warning, German U-Boats sank nearly 100,000 GRT per month, an average of 1.9 ships daily.
[
On 10 April 1915 the British steamer ''Harpalyce'', a Belgian relief ship and clearly marked as such, was torpedoed without warning by near the North Hinder lightship, just outside the strip of sea declared safe by von Pohl. The ship had been en route for America to collect food for starving Belgians, and its sinking outraged American citizens already unhappy at the death of Leon C. Thrasher, drowned when was sunk on 28 March 1915 by ( Thrasher incident).
]
RMS ''Lusitania''
On 7 May 1915, the liner was torpedoed by , off the Old Head of Kinsale
The Old Head of Kinsale () is a headland near Kinsale, County Cork, Ireland.
A castle has been on the headland since at least the 3rd century, with the current iteration built in 1223. An early lighthouse was established here in the 17th centur ...
, Ireland, and sank in just 18 minutes. Of the 1,959 people aboard, 1,198 were killed, 128 of them US citizens.
Following the incident, the German government attempted to justify it with a range of arguments; nevertheless there was massive outrage in Britain and America, and the British felt that the Americans had to declare war on Germany. However, US President Woodrow Wilson
Thomas Woodrow Wilson (December 28, 1856February 3, 1924) was an American politician and academic who served as the 28th president of the United States from 1913 to 1921. A member of the Democratic Party, Wilson served as the president of ...
refused to overreact, though some believed the massive loss of life caused by the sinking of ''Lusitania'' required a firm response from the US.
When Germany began its U-boat campaign against Britain, Wilson had warned that the US would hold the German government strictly accountable for any violations of American rights. Backed by State Department second-in-command Robert Lansing
Robert Lansing (; October 17, 1864 – October 30, 1928) was an American lawyer and diplomat who served as Counselor to the State Department at the outbreak of World War I, and then as United States Secretary of State under President Woodrow Wils ...
, Wilson made his position clear in three notes to the German government issued on 13 May, 9 June, and 21 July.
The first note affirmed the right of Americans to travel as passengers on merchant ships and called for the Germans to abandon submarine warfare against commercial vessels, whatever flag they sailed under.
In the second note Wilson rejected the German arguments that the British blockade was illegal, and was a cruel and deadly attack on innocent civilians, and their charge that ''Lusitania'' had been carrying munitions. Secretary of State William Jennings Bryan
William Jennings Bryan (March 19, 1860 – July 26, 1925) was an American lawyer, orator and politician. Beginning in 1896, he emerged as a dominant force in the History of the Democratic Party (United States), Democratic Party, running ...
considered Wilson's second note too provocative and resigned in protest after failing to have it moderated.
The third note, of 21 July, issued an ultimatum, to the effect that the US would regard any subsequent sinkings as "deliberately unfriendly". While the American public and leadership were not ready for war, the path to an eventual declaration of war had been set as a result of the sinking of ''Lusitania''.
Submarine minelayers
The appearance of new minefields off the east coast of Britain in June 1915 puzzled the Royal Navy due to the waters being very busy, and was blamed initially on neutral fishing boats. However, on 2 July the small coaster ''Cottingham'' accidentally ran down the small coastal U-boat off Great Yarmouth
Great Yarmouth (), often called Yarmouth, is a seaside town and unparished area in, and the main administrative centre of, the Borough of Great Yarmouth in Norfolk, England; it straddles the River Yare and is located east of Norwich. A pop ...
, and when she was salvaged she was found to be a submarine minelayer, fitted with twelve mines in six launching chutes.
On 21 August became the first submarine minelayer to penetrate into the English Channel, laying 12 mines off Boulogne, one of which sank the steamship ''William Dawson'' the same day. ''UC-5'' laid 6 more mines off Boulogne and Folkestone
Folkestone ( ) is a port town on the English Channel, in Kent, south-east England. The town lies on the southern edge of the North Downs at a valley between two cliffs. It was an important harbour and shipping port for most of the 19th and 20t ...
on 7 September, one of which sank the cable layer ''Monarch''. Further mines were laid off the southeast coast by , , , and .
SS ''Arabic''
On 19 August 1915, ''U-24'' sank the White Star liner , outward bound for America, south of Kinsale
Kinsale ( ; ) is a historic port and fishing town in County Cork, Ireland. Located approximately south of Cork City on the southeast coast near the Old Head of Kinsale, it sits at the mouth of the River Bandon, and has a population of 5,281 (a ...
. He fired a single torpedo which struck the liner aft, and she sank within 10 minutes, with the loss of 44 passengers and crew, 3 of whom were American. Following speculation that the US would sever relations with Germany,
on 28 August the Chancellor issued new orders to submarine commanders and relayed them to Washington. The new orders stated that until further notice, all passenger ships could only be sunk after warning and the saving of passengers and crews. This proved unacceptable to the Naval High Command, and on 18 September the High Seas flotillas were withdrawn from the commerce war.
Dardanelles Operations
The German Navy sent their first submarines to the Mediterranean in response to the Anglo-French Dardanelles campaign, after it became obvious that their Austro-Hungarian allies could do little against it with their small submarine force, which nevertheless was successful in defending the Adriatic
The Adriatic Sea () is a body of water separating the Italian Peninsula from the Balkans, Balkan Peninsula. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Sea) ...
. The first U-boats sent, ''U-21'' and the two small coastal boats, and , achieved initial success, ''U-21'' sinking the Royal Navy pre-dreadnought battleships and on 25 and 27 May, respectively, on her way to Constantinople, but ran into severe limitations in the Dardanelles, where swarms of small craft and extensive anti-submarine netting and booms restricted their movements.
By the end of June 1915, the Germans had assembled a further three prefabricated Type UB I submarines at Pola, two of which were to be transferred to the Austro-Hungarian Navy. They were also assembling three Type UC I minelaying submarines, which were ordered converted into transports to carry small quantities of critical supplies to Turkey.
Mediterranean operations
The Mediterranean was an attractive theater of operations to the German Naval Command; a significant proportion of British imports passed through it, it was critical to French and Italian trade, and submarines would be able to operate effectively in it even in autumn and winter when poor weather hampered Atlantic and North Sea operations. Additionally, there were certain choke points through which shipping had to pass, such as the Suez Canal
The Suez Canal ( arz, قَنَاةُ ٱلسُّوَيْسِ, ') is an artificial sea-level waterway in Egypt, connecting the Mediterranean Sea to the Red Sea through the Isthmus of Suez and dividing Africa and Asia. The long canal is a popular ...
, Malta, Crete
Crete ( el, Κρήτη, translit=, Modern: , Ancient: ) is the largest and most populous of the Greek islands, the 88th largest island in the world and the fifth largest island in the Mediterranean Sea, after Sicily, Sardinia, Cyprus, and ...
, and Gibraltar
)
, anthem = " God Save the King"
, song = " Gibraltar Anthem"
, image_map = Gibraltar location in Europe.svg
, map_alt = Location of Gibraltar in Europe
, map_caption = United Kingdom shown in pale green
, mapsize =
, image_map2 = Gib ...
. Finally, the Mediterranean offered the advantage that fewer ships of neutral powers (such as the US or Brazil) would be encountered.
Throughout the summer, the German navy assembled a force of 4 U-boats at Cattaro
Kotor (Montenegrin Cyrillic: Котор, ), historically known as Cattaro (from Italian: ), is a coastal town in Montenegro. It is located in a secluded part of the Bay of Kotor. The city has a population of 13,510 and is the administrative ...
for operations against commerce in the Mediterranean. The campaign got underway in October 1915, when ''U-33'' and ''U-39'', followed later by ''U-35'', were ordered to attack the approaches to Salonika
Thessaloniki (; el, Θεσσαλονίκη, , also known as Thessalonica (), Saloniki, or Salonica (), is the second-largest city in Greece, with over one million inhabitants in its metropolitan area, and the capital of the geographic region of ...
and Kavalla
Kavala ( el, Καβάλα, ''Kavála'' ) is a city in northern Greece, the principal seaport of eastern Macedonia and the capital of Kavala regional unit.
It is situated on the Bay of Kavala, across from the island of Thasos and on the Egnat ...
. That month, 18 ships were sunk, for a total of 63,848 tons. It was decided the same month that further reinforcements were called for, and the large U-boat, sailed for Cattaro. Since Germany was not yet at war with Italy, even though Austria was, German U-boats were ordered to refrain from attacking Italian shipping in the eastern Mediterranean. When operating in the west, up to the line of Cape Matapan
Cape Matapan ( el, Κάβο Ματαπάς, Maniot dialect: Ματαπά), also named as Cape Tainaron or Taenarum ( el, Ακρωτήριον Ταίναρον), or Cape Tenaro, is situated at the end of the Mani Peninsula, Greece. Cape Matapa ...
, German U-boats flew the Austrian flag, and a sinking without warning policy was adopted, since large merchant ships could be attacked on the suspicion of being transports or auxiliary cruisers.
The German Admiralty also decided that the Type UB II submarine would be ideal for Mediterranean service. Since these were too large to be shipped in sections by rail to Pola like the Type UB I, the materials for their construction and German workers to assemble them were sent instead. This meant a shortage of workers to complete U-boats for service in home waters, but it seemed justified by the successes in the Mediterranean in November, when 44 ships were sunk, for a total of 155,882 tons. The total in December fell to 17 ships (73,741 tons) which was still over half the total tonnage sunk in all theaters of operation at the time.
In November 1915, ''U-38'' caused a diplomatic incident
This is a list of ''Yes Minister'' and ''Yes, Prime Minister'' episodes.
Thirty-eight episodes were made in total, running from 1980 to 1988. This includes a one-hour special that aired in 1984. All other episodes were a half-hour in length. ...
when she sank the Italian steamer while sailing under the Austrian flag, and the loss of nine American citizens caused the "sinking without warning" policy to be suspended in April 1916 until the resumption of unrestricted submarine warfare in 1917. A similar incident in March 1916 became a contributing factor in Italy's decision to declare war on Germany in August 1916.
Central countermeasures
Allied countermeasures during this period had mixed success.
Defensive measures, such as arming merchant ships, and advising them to either run, or turn towards the U-boat in order to ram, or force it to submerge, were the most effective.
From arming ships for self-defence, the next step was arming ships for the purpose of engaging the U-boats in gun battles; two U-boats were sunk in 1915 whilst attacking trawlers so fitted. The following step was to arm and man ships with hidden guns to do so, the so-called Q ship
Q-ships, also known as Q-boats, decoy vessels, special service ships, or mystery ships, were heavily armed merchant ships with concealed weaponry, designed to lure submarines into making surface attacks. This gave Q-ships the chance to open f ...
. A variant on the idea was to equip small vessels with a submarine escort. In 1915, two U-boats were sunk by Q-ships, and two more by submarines accompanying trawlers.[Tarrant p24]
Offensive measures were less effective; efforts were made to use nets to find submerged U-boats, and explosive sweeps to destroy them, but these were largely failures.
Attempts were also made to close routes like the Straits of Dover with boom nets and minefields, the so-called Dover Barrage
Dover () is a town and major ferry port in Kent, South East England. It faces France across the Strait of Dover, the narrowest part of the English Channel at from Cap Gris Nez in France. It lies south-east of Canterbury and east of Maidston ...
; to lay minefields around U-boat bases, and station submarines on patrol to catch them leaving or entering port. These measures required a huge expenditure of effort and material, but met with little success. Just two U-boats were sunk by these measures in 1915.
At the beginning of this period the British Merchant Marine had a shipping fleet totaling of 21 million GRT.
In six months of unrestricted submarine warfare U-boats sank million tons of Allied shipping, scarcely denting the British merchant fleet; whilst new building, and additions from ships seized, had more than made up this loss.
On the other hand, serious offence had been given to neutrals such as Norway and the Netherlands, and brought the United States to the brink of war. This failure, and the various restrictions imposed on the U-boat Arm in the Atlantic area largely brought the campaign there to a halt, although it continued with little hindrance in the Mediterranean and elsewhere, where there was less likelihood of offending neutrals.
Given the ineffectiveness of early countermeasures, in 1917 Britain and in 1918 America adopted dazzle camouflage
Dazzle camouflage, also known as razzle dazzle (in the U.S.) or dazzle painting, is a family of ship camouflage that was used extensively in World War I, and to a lesser extent in World War II and afterwards. Credited to the British marine ar ...
to attempt to reduce shipping losses to torpedoes. The results in both cases were inconclusive.
Depth charges
The depth charge, or "dropping mine" as it was initially named, was first mooted in 1910, and developed into practicality when the British Royal Navy's Commander in Chief, Admiral of the Fleet Sir George Callaghan, requested its production in 1914. Design work was carried out by Herbert Taylor at HMS ''Vernon'' Torpedo and Mine School in Portsmouth
Portsmouth ( ) is a port and city in the ceremonial county of Hampshire in southern England. The city of Portsmouth has been a unitary authority since 1 April 1997 and is administered by Portsmouth City Council.
Portsmouth is the most dens ...
, England, and the first effective depth charge, the "Type D", became available in January 1916.
Anti-submarine vessels initially carried only two depth charges, to be released from a chute at the stern of the ship. The first success was the sinking of off Kerry
Kerry or Kerri may refer to:
* Kerry (name), a given name and surname of Gaelic origin (including a list of people with the name)
Places
* Kerry, Queensland, Australia
* County Kerry, Ireland
** Kerry Airport, an international airport in Count ...
, Ireland, on 22 March 1916 by the Q-ship
Q-ships, also known as Q-boats, decoy vessels, special service ships, or mystery ships, were heavily armed merchant ships with concealed weaponry, designed to lure submarines into making surface attacks. This gave Q-ships the chance to open f ...
. Germany became aware of the depth charge following unsuccessful attacks on on 15 April 1916, and on 20 April. and were the only other submarines sunk by depth charges during 1916.[Tarrant, V.E., ''The U-Boat Offensive 1914–1945'', New York, New York: Sterling Publishing Company, 1989, , p. 27]
1916: The High Seas Fleet; Mediterranean, American, Arctic and Black Sea waters
In support of the High Seas Fleet
In 1916 the German Navy again tried to use the U-boats to erode the Grand Fleet's numerical superiority; they staged operations to lure the Grand Fleet into a U-boat trap. Because the U-boats were much slower than the battle fleet, these operations required U-boat patrol lines to be set up in advance; then the battle fleet manoeuvred to draw the Grand Fleet onto them.
Several of these operations were staged, in March and April 1916, but with no success. Ironically, the major fleet action which did take place, the Battle of Jutland
The Battle of Jutland (german: Skagerrakschlacht, the Battle of the Skagerrak) was a naval battle fought between Britain's Royal Navy Grand Fleet, under Admiral John Jellicoe, 1st Earl Jellicoe, Sir John Jellicoe, and the Imperial German Navy ...
, in May 1916, saw no U-boat involvement at all; the fleets met and engaged largely by chance, and there were no U-boat patrols anywhere near the battle area. A further series of operations, in August and October 1916, were similarly unfruitful, and the strategy was abandoned in favor of resuming commerce warfare.
The British were well aware of the risk of U-boat traps to the Grand Fleet, although they had no means of knowing where these might lie. However Jellicoe had developed a tactical response to the problem (which, in the event, was never tested). Faced with a German fleet that turned away, he would assume a submarine trap, and decline to follow, but would move at high speed to the flank, before deploying or opening fire; the aim of this would be to fight the battle away from the ground chosen by his enemy, and forcing any U-boats present to surface if they intended to follow.
Mediterranean waters
During 1916 the commerce war continued unabated in the Mediterranean. Allied countermeasures were largely ineffective; the complex arrangements for co-operation between the various navies meant a fragmented and unco-ordinated response, while the main remedy favored by the Allies for the U-boat menace, the Otranto Barrage
The Otranto Barrage was an Allied naval blockade of the Otranto Straits between Brindisi in Italy and Corfu on the Greek side of the Adriatic Sea in the First World War. The blockade was intended to prevent the Austro-Hungarian Navy from escap ...
, was of little value.
Just two U-boats were caught in the barrage in all the time it was in operation; meanwhile merchant shipping suffered huge losses. In 1916 the Allies lost 415 ships, of 1,045,058 GRT, half of all Allied ships sunk in all theatres.
Eight of the top dozen U-boat aces served in the Pola flotilla, including the highest scoring commander of all, Lothar von Arnauld de la Perière
''Vizeadmiral'' Lothar von Arnauld de la Perière (; March 18, 1886 – February 24, 1941), born in Posen, Prussia, and of French-German descent, was a German U-boat commander during World War I. With 194 ships and sunk, he is the most successfu ...
.
American waters
In 1916 the Germans completed two submarine merchant vessels, to be used as blockade runners. The aim was to use them to carry high value goods to neutral nations such as the US, which still maintained a strict neutrality, and was prepared to trade with Germany as with any other nation. The first of these vessels, ''Deutschland'', sailed in summer 1916 and made a favorable impact on US public opinion. She made a second equally successful voyage in autumn of that year. Her sister, ''Bremen'', was less fortunate; she disappeared on her maiden voyage, the cause of her loss unknown.
A less favorable impression was made by the cruise of under K/L Hans Rose
Hans Rose (April 18, 1885 – December 6, 1969) was one of the most successful and highly decorated German U-boat commanders in the '' Kaiserliche Marine'' during . He sank 79 ships for a total of during the war.
World War I
In September 1916, ...
. After refuelling at Newport, Rhode Island
Newport is an American seaside city on Aquidneck Island in Newport County, Rhode Island. It is located in Narragansett Bay, approximately southeast of Providence, Rhode Island, Providence, south of Fall River, Massachusetts, south of Boston, ...
, Rose raided Allied shipping off the coast of Canada and the United States. Although this was in international waters, and Rose scrupulously followed international law, the action was seen as an affront to the US, particularly when US warships were forced to stand aside while merchant ships nearby were sunk.
Arctic waters
In autumn 1916, U-boats of the High Seas flotilla attacked shipping bound for Russia
Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...
. Five U-boats operated in the Barents Sea
The Barents Sea ( , also ; no, Barentshavet, ; russian: Баренцево море, Barentsevo More) is a marginal sea of the Arctic Ocean, located off the northern coasts of Norway and Russia and divided between Norwegian and Russian territo ...
between North Cape and the Kola inlet
Kola Bay (russian: Кольский залив) or Murmansk Fjord is a 57-km-long fjord of the Barents Sea that cuts into the northern part of the Kola Peninsula. It is up to 7 km wide and has a depth of 200 to 300 metres. The Tuloma, Rosta ...
. Also, the two UE1-class minelaying boats laid minefields in the White Sea
The White Sea (russian: Белое море, ''Béloye móre''; Karelian and fi, Vienanmeri, lit. Dvina Sea; yrk, Сэрако ямʼ, ''Serako yam'') is a southern inlet of the Barents Sea located on the northwest coast of Russia. It is su ...
. These boats sank 34 ships (19 of them Norwegian) before winter ice closed the area for operations.
One of the ships sunk near the Norwegian coast was the Romanian merchant ''Bistrița'', sunk by ''U-43'' on 11 November. Before sinking the ship, the captain of the U-boat allowed the ship's crew to take refuge in his submarine, then later he handed over the crew to a Russian sailing ship which took them to Vardø
( fi, Vuoreija, fkv, Vuorea, se, Várggát) is a municipality in Troms og Finnmark county in the extreme northeastern part of Norway. Vardø is the easternmost town in Norway, more to the east than Saint Petersburg or Istanbul. The administra ...
. From there, they were eventually repatriated.
Black Sea waters
The Constantinople Flotilla was established in May 1915 and operated U-boats in the Black Sea
The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Roma ...
. Bulgaria joined the campaign in May 1916, when the German submarine ''UB-8'' was commissioned by the Bulgarian Navy as ''Podvodnik''. In three years of operation, the Flotilla sank ships totalling 117,093 GRT.
'' UB-45'' was lost in November 1916 and '' UB-46'' in December, both sunk by Russian mines. In addition, ''UB-7'' was reportedly sunk by Russian aircraft in October.
Throughout September and October 1916, the main task of the submarines '' UB-42'' and '' UB-14'' was patrolling the Russian and Romanian coasts, from Constanța
Constanța (, ; ; rup, Custantsa; bg, Кюстенджа, Kyustendzha, or bg, Констанца, Konstantsa, label=none; el, Κωνστάντζα, Kōnstántza, or el, Κωνστάντια, Kōnstántia, label=none; tr, Köstence), histo ...
to Sevastopol
Sevastopol (; uk, Севасто́поль, Sevastópolʹ, ; gkm, Σεβαστούπολις, Sevastoúpolis, ; crh, Акъя́р, Aqyár, ), sometimes written Sebastopol, is the largest city in Crimea, and a major port on the Black Sea ...
. On 30 September 1916, near the port of Sulina
Sulina () is a town and free port in Tulcea County, Northern Dobruja, Romania, at the mouth of the Sulina branch of the Danube. It is the easternmost point of Romania.
History
During the mid-Byzantine period, Sulina was a small cove, and in t ...
, ''UB-42'' launched a torpedo at the Romanian torpedo boat '' Smeul'', but missed. The Romanian warship counterattacked, damaging the submarine's periscope and conning tower and forcing her to retreat. In November, the German submarine '' UC-15'' was sent on a minelaying mission off Sulina and never returned, being sunk by her own mines. This was probably caused by an encounter with ''Smeul'', whose captain surprised a German submarine near Sulina in November 1916, the latter reportedly never returning to her base at Varna, Bulgaria
Varna ( bg, Варна, ) is the third-largest List of cities and towns in Bulgaria, city in Bulgaria and the largest city and seaside resort on the Bulgarian Black Sea Coast and in the Northern Bulgaria region. Situated strategically in the ...
. This could only be ''UC-15'', whose systems most likely malfunctioned after being forced to submerge in the shallow waters, upon encountering the Romanian torpedo boat.
1917: Resumption of unrestricted submarine warfare
On 22 December 1916, Admiral von Holtzendorff composed a memorandum which became the pivotal document for Germany's resumption of unrestricted U-boat warfare in 1917. Holtzendorff proposed breaking Britain's back by sinking 600,000 tons of shipping per month, based on a February 1916 study by Dr. Richard Fuss, who had postulated that if merchant shipping was sunk at such a rate, Britain would run out of shipping and be forced to sue for peace within six months, well before the Americans could act. Even if the "disorganized and undisciplined" Americans did intervene, Holtzendorff assured the Kaiser, "I give your Majesty my word as an officer, that not one American will land on the Continent."
On 9 January 1917, the Kaiser met with Chancellor Bethmann-Hollweg and military leaders at Schloss Pless to discuss measures to resolve Germany's increasingly grim war situation; its military campaign in France had bogged down, and with Allied divisions outnumbering German ones by 190 to 150, there was a real possibility of a successful Allied offensive. Meanwhile, the German navy was bottled up in its home port of Kiel, and the British blockade had caused a food scarcity that was in turn causing deaths due to malnutrition. The military staff urged the Kaiser to unleash the submarine fleet on shipping travelling to Britain, Hindenburg advising the Kaiser that "The war must be brought to an end by whatever means as soon as possible." On 31 January, the Kaiser duly signed the order for unrestricted submarine warfare to resume effective 1 February; Bethmann-Hollweg, who had opposed the decision, said "Germany is finished".
On 27 January, Admiral Beatty observed that "The real crux lies in whether we blockade the enemy to his knees, or whether he does the same to us."
Germany had 105 submarines ready for action on 1 February: 46 in the High Seas Fleet; 23 in Flanders; 23 in the Mediterranean; 10 in the Baltic; and 3 at Constantinople. Fresh construction ensured that, despite losses, at least 120 submarines would be available for the rest of 1917. The campaign was initially a great success, nearly 500,000 tons of shipping being sunk in both February and March, and 860,000 tons in April, when Britain's supplies of wheat shrank to six weeks worth. In May losses exceeded 600,000 tons, and in June 700,000. Germany had lost only nine submarines in the first three months of the campaign.[
On 1 February, near ]Gironde
Gironde ( US usually, , ; oc, Gironda, ) is the largest department in the Nouvelle-Aquitaine region of Southwestern France. Named after the Gironde estuary, a major waterway, its prefecture is Bordeaux. In 2019, it had a population of 1,62 ...
, a U-boat surfaced near the Romanian merchant ''București'', the latter being armed with two 120 mm guns. A short artillery duel ensued, between the merchant's aft gun (manned by officer Ciocaș Mihail) and the submarine's deck gun. Eventually, a shell from the merchant's gun fell 50 meters away from the submarine, prompting the U-boat to submerge and retreat.
On 3 February, in response to the new submarine campaign, President Wilson severed all diplomatic relations with Germany, and the US Congress declared war on 6 April.
Allied response
The new policy of unrestricted submarine warfare was initially a success. In January 1917, prior to the campaign, Britain lost 49 ships; in February, after it opened, 105; and in March, 147. In March a full 25% of all Britain-bound shipping was sunk.
At first, the British Admiralty failed to respond effectively to the German offensive. Despite the proven success of troop convoys earlier in the war, the Channel convoys between England and France, and the Dutch, French, and Scandinavian convoys in the North Sea, they initially refused to consider widespread convoying or escorting. Convoying imposed severe delays on shipping, and was believed to be counterproductive, amounting to a loss of carrying capacity greater than the loss inflicted by the U-Boats. It was disliked by both merchant and naval captains, and derided as a defensive measure. It was not until 27 April that the Admiralty endorsed the convoy system, the first convoy sailing from Gibraltar on 10 May.[
In April, US Rear Admiral ]William Sims
William Sowden Sims (October 15, 1858 – September 28, 1936) was an admiral in the United States Navy who fought during the late 19th and early 20th centuries to modernize the navy. During World War I, he commanded all United States naval force ...
arrived in London as US Naval Liaison. He was dismayed to be informed by the Admiralty that Germany would win the war if its submarines went unchecked, and cabled Washington to have USN destroyers despatched to Queenstown, Ireland, from where they were to patrol to the west.[
As merchantmen from Allied countries were sunk, Brazilian ships took over routes that had been vacated. However, this led the Brazilian vessels into waters patrolled by ]U-boats
U-boats were naval submarines operated by Germany, particularly in the First and Second World Wars. Although at times they were efficient fleet weapons against enemy naval warships, they were most effectively used in an economic warfare rol ...
. When coupled with Germany's policy of unrestricted submarine warfare, the result was that Brazilian ships were soon lost, which drove the country closer to declaring war on the Central Powers.
In May and June a regular system of transatlantic convoys were established, and after July the monthly losses never exceeded 500,000 tons, although they remained above 300,000 tons for the remainder of 1917. Convoying was an immediate success; on whichever routes it was introduced it resulted in a drop in shipping losses, with the U-boats seeking out easier prey. It also brought warships escorting the convoys in contact with attacking U-boats, leading to an increase in U-boats destroyed.
German submarine losses were between 5 and 10 each month, and they soon realised the need to increase production, even at the expense of building surface warships. However, production was delayed by labour and material shortages.[
The ]Allied Maritime Transport Council The Allied Maritime Transport Council (AMTC) was an international agency created during World War I to coordinate shipping between the allied powers of France, Italy, Great Britain, and the United States. The council (based in London) was formed at ...
was established on 3 November 1917, bringing together representatives from the British Empire
The British Empire was composed of the dominions, colonies, protectorates, mandates, and other territories ruled or administered by the United Kingdom and its predecessor states. It began with the overseas possessions and trading posts esta ...
, the United States, France and Italy to provide an 'international administration' for more efficient management of shipping. This initiative lead the civil action which complemented the naval action in response to the U-boat campaign, and which consisted of the efficient organisation of both shipping and of the distribution of supplies, such that the utility of every ton of imported goods was used to the maximum effectiveness.
1918: The last year
At the end of 1917 Allied shipping losses stood at over 6 million GRT for the year overall.
However monthly shipping losses had dropped to around 300,000 GRT, and never rose to the levels suffered in spring 1917.[Tarrant p149]
With the establishment of a comprehensive convoy system, Allied shipping losses fell to non-critical levels, while U-boat losses increased alarmingly. From 48 boats lost in the years up to February 1917, a further 61 were lost by the end of the year.
The logical response to the convoy system, which concentrated forces for the defence, was to similarly concentrate the attacking force. The U-boat arm did not succeed in World War I in developing such a response. Just one attempt was made to operate a group, to mount a pack attack on any convoy encountered; 6 U-boats sailed in May 1918 as a group, commanded by K/L Rucker in .
They encountered several home-bound convoys and succeeded in sinking 3 ships, but at the loss of 2 of their number, including ''U-103'', which was rammed by the troopship ''Olympic''. Rucker had found it next to impossible to exercise control from his position at sea, and the loss ratio discouraged any further experiments.
U-cruisers
Late in the war, the German high command decided to take the submarine war to the coast of the US, using the large Type U-151 and Type U-139 U-boats. The Type U-151 carried 18 torpedoes (24 torpedoes on the Type U-139) and two 150 mm deck guns, and had a range of around . Seven Type U-151 and three Type U-139 had been built, the Type U-151 originally as large merchant U-boats for shipping material to and from locations otherwise denied German surface ship
Surface combatants (or surface ships or surface vessels) are a subset of naval warships which are designed for warfare on the surface of the water, with their own weapons and armed forces. They are generally ships built to fight other ships, subma ...
s, such as the United States, and 6 Type U-151 were refitted for war duty in 1917. The Type U-139 were the largest U-boats of World War I.
American campaign
departed Kiel on 14 April 1918 commanded by Korvettenkapitän Heinrich von Nostitz und Jänckendorff, her mission to attack American shipping. She arrived in Chesapeake Bay
The Chesapeake Bay ( ) is the largest estuary in the United States. The Bay is located in the Mid-Atlantic (United States), Mid-Atlantic region and is primarily separated from the Atlantic Ocean by the Delmarva Peninsula (including the parts: the ...
on 21 May where she laid mines off the Delaware capes, and cut the submerged telegraph cables which connected New York with Nova Scotia
Nova Scotia ( ; ; ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. Nova Scotia is Latin for "New Scotland".
Most of the population are native Eng ...
. On 25 May she stopped three US schooners off Virginia, took their crews prisoner, and sank the three ships by gunfire. On 2 June 1918, known to some historians as "Black Sunday", ''U-151'' sank six US ships and damaged two others off the coast of New Jersey in the space of a few hours. The next day the tanker ''Herbert L. Pratt'' struck a mine previously laid by ''U-151'' in the area but was later salvaged. Only 13 people died in the seven sinkings, their deaths caused by a capsized lifeboat. She returned to Kiel on 20 July 1918 after a 94-day cruise in which she had covered a distance of , sunk 23 ships totalling 61,000 tons, and had laid mines responsible for the sinking of another 4 vessels.
Encouraged by the success of ''U-151'', , , and the large Type 139, U-cruisers were despatched on similar missions, but the US Navy was now ready for them, and the hunting was not as good. was lost with all hands on the return voyage when she struck a mine off Bergen, Norway, on 25 September 1918. Another trio of long-range submarines, , , and U-cruiser were making their way across the Atlantic in November 1918 when the war ended.
A few of the U-cruisers also made long voyages south to the Azores and the African coast, where they operated generally unmolested against shipping operating in the area, though one, , was torpedoed by the British submarine off the coast of Portugal in May 1918.
July 1918 witnessed the Attack on Orleans
The Attack on Orleans was a naval and air action during World War I on 21 July 1918 when a German submarine fired on a small convoy of barges led by a tugboat off Orleans, Massachusetts, on the eastern coast of the Cape Cod peninsula. Several ...
when a U-boat sunk four barges and a tugboat off the coast of Cape Cod
Cape Cod is a peninsula extending into the Atlantic Ocean from the southeastern corner of mainland Massachusetts, in the northeastern United States. Its historic, maritime character and ample beaches attract heavy tourism during the summer mont ...
by the town of Orleans. The U-boat fired on the town ineffectually for about an hour before it was fought off by two Navy planes. It was the first attack involving a foreign power's artillery against US soil since the Mexican–American War
The Mexican–American War, also known in the United States as the Mexican War and in Mexico as the (''United States intervention in Mexico''), was an armed conflict between the United States and Mexico from 1846 to 1848. It followed the 1 ...
.
Final countermeasures
By 1918 the Allied anti-submarine measures had continued to become more effective.
Aircraft began to play an increasingly effective role in patrolling large areas quickly. While they had little effect when attacking (only one U-boat was confirmed as sunk by air attack) the presence of aircraft forced the U-boat to dive, becoming blind and immobile, or risk the air patrol summoning hunting warships to the scene. During 1918 no convoy escorted by air patrol lost a ship, and U-boats were forced increasingly to operate at night or beyond aircraft range.
In 1918 the USN embarked on a mammoth scheme to create a barrage across the routes exiting the North Sea. The North Sea Mine Barrage
The North Sea Mine Barrage, also known as the Northern Barrage, was a large minefield laid easterly from the Orkney Islands to Norway by the United States Navy (assisted by the Royal Navy) during World War I. The objective was to inhibit the m ...
saw the laying of over 70,000 mines during the summer of 1918. From September to November 1918 6 U-boats were sunk by this measure.
The RN also developed the R-class submarine, designed as a hunter-killer vessel, with a high underwater speed and sophisticated hydrophone system. These came too late to see action, however, and no successes were recorded by them.
By the end of 1918, Allied shipping losses were 2¾ million GRT for the year overall (averaging 323,000 tons through March and declining thereafter) at a cost of 69 submarines, the U-boat Arm's worst year.
United States Navy in the Atlantic and Mediterranean
During the Great War United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...
warships were deployed to both the Atlantic and Mediterranean with the primary objective of fighting German submarines and escorting convoys. American participation commenced with an event known as the "Return of the ''Mayflower''", when the first six destroyers arrived at Queenstown, Ireland
Cobh ( ,), known from 1849 until 1920 as Queenstown, is a seaport town on the south coast of County Cork, Ireland. With a population of around 13,000 inhabitants, Cobh is on the south side of Great Island in Cork Harbour and home to Ireland's ...
in May 1917. Despite their long journey, when asked when they would be ready to go on patrol, the squadron commander replied "We are ready now". Essentially all available American destroyers and much of the submarine force were deployed in 1917–18, with bases including Queenstown, Bantry Bay
Bantry Bay ( ga, Cuan Baoi / Inbhear na mBárc / Bádh Bheanntraighe) is a bay located in County Cork, Ireland. The bay runs approximately from northeast to southwest into the Atlantic Ocean. It is approximately 3-to-4 km (1.8-to-2.5 mil ...
, the Azores
)
, motto =( en, "Rather die free than subjected in peace")
, anthem= ( en, "Anthem of the Azores")
, image_map=Locator_map_of_Azores_in_EU.svg
, map_alt=Location of the Azores within the European Union
, map_caption=Location of the Azores wi ...
, and other locations. Many contacts and attacks were made in the Atlantic and Mediterranean, though only two U-boats were sunk or disabled by American action. An American auxiliary cruiser heavily damaged a U-boat during the action of 4 April 1918. As a result, the Germans sailed directly for Spain where they scuttled their boat. American submarine chasers also engaged in one battle
A battle is an occurrence of combat in warfare between opposing military units of any number or size. A war usually consists of multiple battles. In general, a battle is a military engagement that is well defined in duration, area, and force ...
against Austro-Hungarian forces during the war. Though their participation in the conflict was intended as a counter-submarine effort, they were engaged by enemy shore batteries, charted a path through a minefield and helped sink two Austro-Hungarian destroyers at the naval base of Durazzo, Albania.
Japanese participation
Beginning in April 1917, Japan, an ally of the United Kingdom, sent a total of 14 destroyers to the Mediterranean with cruiser flagships which were based at Malta and played an important part in escorting convoys to guard them against enemy submarines. The Japanese ships were very effective in patrol and anti-submarine activity. However, of the 9 Austro-Hungarian navy submarines lost to enemy action, 5 were sunk by Italian navy units (''U-13'', ''U-10'', ''U-16'', ''U-20'', and ''U-23''), 1 by Italian and French units (''U-30''), 1 by Royal Navy units (''U-3''), while none were sunk by the Japanese navy, which lost one destroyer (, torpedoed by ''U-27'').
Brazilian participation
On 21 December 1917 the British government requested that a Brazilian naval force of light cruisers be placed under Royal Navy control and a squadron comprising the cruisers ''Rio Grande do Sul'' and ''Bahia'', the destroyers ''Paraíba'', ''Rio Grande do Norte'', ''Piauí'', and ''Santa Catarina'', and the support ship ''Belmonte'' and the ocean-going tug ''Laurindo Pitta'' was formed, designated the ''Divisão Naval em Operações de Guerra'' ("Naval Division in War Operations
War is an intense armed conflict between states, governments, societies, or paramilitary groups such as mercenaries, insurgents, and militias. It is generally characterized by extreme violence, destruction, and mortality, using regular ...
"). The DNOG sailed on 31 July 1918 from Fernando de Noronha
Fernando de Noronha () is an archipelago in the Atlantic Ocean, part of the State of Pernambuco, Brazil, and located off the Brazilian coast. It consists of 21 islands and islets, extending over an area of . Only the eponymous main island is inha ...
for Sierra Leone
Sierra Leone,)]. officially the Republic of Sierra Leone, is a country on the southwest coast of West Africa. It is bordered by Liberia to the southeast and Guinea surrounds the northern half of the nation. Covering a total area of , Sierra ...
, arriving at Freetown on 9 August, and sailing onwards to its new base of operations, Dakar
Dakar ( ; ; wo, Ndakaaru) (from daqaar ''tamarind''), is the capital and largest city of Senegal. The city of Dakar proper has a population of 1,030,594, whereas the population of the Dakar metropolitan area is estimated at 3.94 million in 2 ...
, on 23 August. On the night of 25 August the division believed it had been attacked by a U-boat when the auxiliary cruiser ''Belmonte'' sighted a torpedo track. The purported submarine was depth-charged, fired on, and reportedly sunk by the ''Rio Grande do Norte'', but the sinking was never confirmed.
The DNOG patrolled the Dakar-Cape Verde
, national_anthem = ()
, official_languages = Portuguese
, national_languages = Cape Verdean Creole
, capital = Praia
, coordinates =
, largest_city = capital
, demonym ...
-Gibraltar triangle, which was suspected to be used by U-boats waiting on convoys, until 3 November 1918 when it sailed for Gibraltar to begin operations in the Mediterranean, with the exception of the ''Rio Grande do Sul'', ''Rio Grande do Norte'', and ''Belmonte''. The Division arrived at Gibraltar on 10 November; while passing through the Straits of Gibraltar, they mistook three USN subchasers for U-boats but no damage was caused.
Aftermath
By mid-1918, U-boat losses had reached unacceptable levels, and the morale of their crews had drastically deteriorated; by the autumn it became clear that the Central Powers could not win the war.
The Allies insisted that an essential precondition of any armistice was that Germany surrender all her submarines, and on 24 October 1918 all German U-boats were ordered to cease offensive operations and return to their home ports. The Allies stipulated that all seaworthy submarines were to be surrendered to them and those in shipyards be broken up.
More than 160 U-boats surrendered at Harwich
Harwich is a town in Essex, England, and one of the Haven ports on the North Sea coast. It is in the Tendring district. Nearby places include Felixstowe to the north-east, Ipswich to the north-west, Colchester to the south-west and Clacton-on- ...
, Essex in November 1918. Overseen by Rear Admiral Sir Reginald Tyrwhitt, commanding officer of the Harwich fleet, the German crews were loaded on to transport ships to be sent home without being allowed to set foot on British soil. Some of the U-boats were sent to places such as Liverpool
Liverpool is a city and metropolitan borough in Merseyside, England. With a population of in 2019, it is the 10th largest English district by population and its metropolitan area is the fifth largest in the United Kingdom, with a popul ...
or Brighton
Brighton () is a seaside resort and one of the two main areas of the City of Brighton and Hove in the county of East Sussex, England. It is located south of London.
Archaeological evidence of settlement in the area dates back to the Bronze A ...
to be put on display whilst others were left on the beach.
The last significant role played by U-boats in World War I was the suppression of the German naval mutiny that same month, when they stood ready to "fire without warning on any vessel flying the red flag".
Summary
Allied and Neutral Tonnage sunk by U-boats in World War I
Grand Total 12,850,815 gross tons
Allied losses included 10 battleships, 18 cruisers and several smaller naval vessels.[Micheal Clodfelter, Warfare and Armed Conflicts: A Statistical Encyclopedia of Casualty and Other Figures, 1492–2015, 4th ed., McFarland, 2017, p. 428]
Unrestricted submarine warfare was resumed in February 1917 and the British began full-scale convoying in September 1917. The heaviest losses were suffered in April 1917 when a record 881,027 tons were sunk by the U-boats.
150,000 tons of ''purely British'' shipping were lost in January 1917, and 300,000 tons in February; Allied and neutral losses increased in a similar proportion. In April 525,000 tons of ''British'' shipping were lost. In October 270,000 tons were lost, and in December 170,000 tons were lost. These totals are included in the above figures.
29 U-boat commanders were decorated with the Pour le Mérite
The ' (; , ) is an order of merit (german: Verdienstorden) established in 1740 by Frederick the Great, King Frederick II of Prussia. The was awarded as both a military and civil honour and ranked, along with the Order of the Black Eagle, the Or ...
, the highest German decoration for gallantry for officers. 12 U-boat crewmen received the Goldene Militär-Verdienst-Kreuz, the highest bravery award for non-commissioned officers and enlisted men.
The most successful U-boat commanders of World War I were Lothar von Arnauld de la Perière
''Vizeadmiral'' Lothar von Arnauld de la Perière (; March 18, 1886 – February 24, 1941), born in Posen, Prussia, and of French-German descent, was a German U-boat commander during World War I. With 194 ships and sunk, he is the most successfu ...
(189 merchant vessels and two gunboats with 446,708 tons), followed by Walter Forstmann
Walther Forstmann (9 March 1883 – 2 November 1973) was one of the most highly decorated U-boat commanders in the ''Kaiserliche Marine'' during World War I. He also served in the ''Kriegsmarine'' during World War II in different Staff (military), ...
(149 ships with 391,607 tons), and Max Valentiner
Captain Christian August Max Ahlmann Valentiner (15 December 1883 – 19 July 1949) was a German U-boat commander during World War I. He was the third highest-scoring U-boat commander of the war, and was awarded the Pour le Mérite for his achievem ...
(144 ships with 299,482 tons). So far, their records have never been surpassed by anyone in any later conflict.
Sir Joseph Maclay approved four standard designs of merchant ship and placed orders for over 1,000,000 tons of shipping (Britain launched 495,000 tons of shipping in the first half of 1917, but 850,000 tons were sunk in the first quarter alone; by 1918 3,000,000 tons a year were being launched).[Grigg 2002, p48-9]
German Submarine Force 1914–1918
* Total operational boats: 351
* Total sunk in combat: 178 (41 by mines, 30 by depth charges and 13 by Q-ships
Q-ships, also known as Q-boats, decoy vessels, special service ships, or mystery ships, were heavily armed merchant ships with concealed weaponry, designed to lure submarines into making surface attacks. This gave Q-ships the chance to open f ...
)
* Other losses: 39
* Completed after Armistice: 45
* Surrendered to Allies: 179
* Men lost in U-boats: 515 officers and 4894 enlisted men
References
Notes
Bibliography
*
*
*
*
* Grey, Edwyn (1972) ''The Killing Time'' Seeley
* Grigg, John (2002) ''Lloyd George: War Leader, 1916–1918'' Allen Lane, London.
*
*
* Jane's ''Fighting Ships of World War I'' (1919, reprinted 1990) Studio Editions
* Messimer, Dwight (2001) ''Find and Destroy'' Naval Institute
*
*
* Tarrant, V. E. (1989) ''The U-Boat Offensive 1914–1945'' Arms and Armour
*
*
Further reading
*
*
External links
* Abbatiello, John
Atlantic U-boat Campaign
, in
* Karau, Mark D.
Submarines and Submarine Warfare
, in
* ttp://www.worldwar1atsea.net World's Navies in World War 1, Campaigns, Battles, Warship losses
"First Battle of the Atlantic" article
A 44 min. German film from 1917 about a cruise of the German submarine U-35.
Detailed information about German submarines.
original documents, photos and maps about World War I German submarine warfare and British Room 40
Room 40, also known as 40 O.B. (old building; officially part of NID25), was the cryptanalysis section of the British Admiralty during the First World War.
The group, which was formed in October 1914, began when Rear-Admiral Henry Oliver, the ...
Intelligence from The National Archives
National archives are central archives maintained by countries. This article contains a list of national archives.
Among its more important tasks are to ensure the accessibility and preservation of the information produced by governments, both ...
, Kew, Richmond, UK.
Historical footage of U-boats in World War I
europeanfilmgateway.eu
{{World War I
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Campaign World War I
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Naval battles of World War I involving Brazil
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Austria-Hungary in World War I
German Empire in World War I
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Brazil in World War I
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