The Treaty of Windsor was a secret colonial declaration between 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 ...

and

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

in 1899. It was named after the earlier

Treaty of Windsor (1386) The Treaty of Windsor is the diplomatic alliance signed between Portugal and England on 9 May 1386 at Windsor and sealed by the marriage of King John I of Portugal (House of Aviz) to Philippa of Lancaster, daughter of John of Gaunt, 1st Duke ...

though actually signed in London on 14 October 1899 by the British Prime Minister

Lord Salisbury Robert Arthur Talbot Gascoyne-Cecil, 3rd Marquess of Salisbury (; 3 February 183022 August 1903) was a British statesman and Conservative politician who served as Prime Minister of the United Kingdom three times for a total of over thirteen y ...

and the Portuguese ambassador Soveral. Anglo-Portuguese relations in Africa had been strained by the

1890 British Ultimatum The 1890 British Ultimatum was an ultimatum by the British government delivered on 11 January 1890 to the Kingdom of Portugal. The ultimatum forced the retreat of Portuguese military forces from areas which had been claimed by Portugal on the bas ...

which had blocked Portugal from joining its colonies in

Angola , national_anthem = " Angola Avante"() , image_map = , map_caption = , capital = Luanda , religion = , religion_year = 2020 , religion_ref = , coordina ...

and

Mozambique Mozambique (), officially the Republic of Mozambique ( pt, Moçambique or , ; ny, Mozambiki; sw, Msumbiji; ts, Muzambhiki), is a country located in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi ...

across what later became

Malawi Malawi (; or aláwi Tumbuka: ''Malaŵi''), officially the Republic of Malawi, is a landlocked country in Southeastern Africa that was formerly known as Nyasaland. It is bordered by Zambia to the west, Tanzania to the north and northeast ...

Zambia Zambia (), officially the Republic of Zambia, is a landlocked country at the crossroads of Central Africa, Central, Southern Africa, Southern and East Africa, although it is typically referred to as being in Southern Africa at its most cent ...

and

Zimbabwe Zimbabwe (), officially the Republic of Zimbabwe, is a landlocked country located in Southeast Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa to the south, Botswana to the south-west, Zambia to the north, and Mozam ...

leading to the

Anglo-Portuguese Treaty of 1891 The Anglo-Portuguese Treaty of 1891 was an agreement between Great Britain and Portugal which fixed the boundaries between the British Central Africa Protectorate, (now Malawi) and the territories administered by the British South Africa Company ...

, and by an Anglo-German understanding in 1898 that, if Portugal relinquished its African colonies, Germany could expand

German South West Africa German South West Africa (german: Deutsch-Südwestafrika) was a colony of the German Empire from 1884 until 1915, though Germany did not officially recognise its loss of this territory until the 1919 Treaty of Versailles. With a total area of ...

northwards and

German East Africa German East Africa (GEA; german: Deutsch-Ostafrika) was a German colony in the African Great Lakes region, which included present-day Burundi, Rwanda, the Tanzania mainland, and the Kionga Triangle, a small region later incorporated into Mozam ...

southwards while Great Britain could expand its

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

n territory eastwards and control Portugal's Atlantic islands. The 1899 declaration reaffirmed former treaties between the two countries, including those of 1642 and 1661. Great Britain agreed to defend Portuguese colonies from their "future and present" enemies. Portugal agreed to not declare neutrality officially in the forthcoming

Second Boer War The Second Boer War ( af, Tweede Vryheidsoorlog, , 11 October 189931 May 1902), also known as the Boer War, the Anglo–Boer War, or the South African War, was a conflict fought between the British Empire and the two Boer Republics (the Sout ...

and to prevent Boer movement of arms and troops through

Lourenço Marques Maputo (), formerly named Lourenço Marques until 1976, is the capital, and largest city of Mozambique. Located near the southern end of the country, it is within of the borders with Eswatini and South Africa. The city has a population of 1,088 ...

and Mozambique to the

Transvaal Transvaal is a historical geographic term associated with land north of (''i.e.'', beyond) the Vaal River in South Africa. A number of states and administrative divisions have carried the name Transvaal. * South African Republic (1856–1902; af, ...

.Douglas L. Wheeler, Walter C. Opello Jr., ''Historical Dictionary of Portugal,'' p.280

References

Portugal–United Kingdom relations Windsor 1899 Windsor 1899 British colonisation in Africa Portuguese colonisation in Africa 19th century in Angola 19th century in Mozambique 19th century in South Africa 1899 in Africa Treaties of the United Kingdom (1801–1922)

Windsor Windsor may refer to: Places Australia * Windsor, New South Wales ** Municipality of Windsor, a former local government area * Windsor, Queensland, a suburb of Brisbane, Queensland **Shire of Windsor, a former local government authority around Wi ...

1899 in Portugal 1899 in the United Kingdom 1899 in British law {{UK-hist-stub