Battle of Mosul (2016–2017)

The Battle of Mosul ( ar, معركة الموصل, ''Ma'rakat al-Mawṣil''; ckb, شەڕی مووسڵ, ''Şeriy Mûsil'') was a major military campaign launched by the Iraqi Government forces with allied militias, the Kurdistan Regional Government, and international forces to retake the city of Mosul from the Islamic State (ISIL), which had seized the city in June 2014. The battle was the world's single largest military operation since the 2003 invasion of Iraq and was considered the toughest urban battle since World War II.

The offensive, dubbed Operation "We Are Coming, Nineveh" (; ''Qadimun Ya Naynawa''), began on 16 October 2016, with forces besieging ISIL-controlled areas in the Nineveh Governorate surrounding Mosul, and continued with Iraqi troops and Peshmerga fighters engaging ISIL on three fronts outside Mosul, going from village to village in the surrounding area in the largest deployment of Iraqi troops since the 2003 invasion of Iraq.

At dawn on 1 November 2016, Iraqi Special Operations Forces entered the city from the east. Met with fierce fighting, the government advance into the city was slowed by elaborate defenses and by the presence of civilians, but the Iraqi Prime Minister Haider al-Abadi declared "full liberation of eastern side of Mosul" on 24 January 2017. Iraqi troops began their offensive to recapture western Mosul on 19 February 2017.

On 9 July 2017, the Iraqi Prime Minister arrived in Mosul to announce the victory over ISIL, and an official declaration of victory was proclaimed on 10 July. However, heavy clashes continued in a final pocket of ISIL resistance in the Old City, for almost another 2 weeks.Sporadic clashes continue in Mosul after victory declared
It was estimated that removing the explosives from Mosul and repairing the city over the next 5 years would require $50 billion (2017 USD), while Mosul's Old City alone would cost about US$1 billion to repair.

The Battle of Mosul was concurrent with the Battle of Sirte (2016) in Libya and the Raqqa campaign (2016–17) conducted by the Syrian Democratic Forces (SDF) against ISIL's capital city and stronghold in Syria.

Background

General background

Mosul is Iraq's second most populous city. It fell to 800–1,500 ISIL militants in June 2014, because of the largely Sunni population's deep distrust of the primarily Shia Iraqi government. It was in the Great Mosque in Mosul that ISIL leader Abu Bakr al-Baghdadi declared the beginning of ISIL's self-proclaimed "caliphate" which spans Iraq and Syria. The original population of 2.5 million fell to approximately 1.5 million after two years of ISIL rule. The city was once extremely diverse, with ethnic minorities including Armenians, Yazidis, Assyrian, Turkmen, and Shabak people, all of whom have suffered under the (majority Sunni Arab) Islamic State. Mosul was the last stronghold of ISIL in Iraq, and the anticipated offensive to reclaim it was promoted as the "mother of all battles."

Preparations for the battle

In the weeks leading up to the ground offensive, the US-led CJTF–OIR coalition bombed ISIL targets, and the Iraqi Army made gradual advances on the city. Royal Air Force's Reaper drones, Typhoons, and Tornados targeted "rocket launchers, ammunition stockpiles, artillery pieces and mortar positions" in the 72 hours before the ground assault began. Leaflets dropped on the city by the Iraqi military advised young male residents to "rise up" against ISIL when the battle began. To prepare defenses against the assault, ISIL operatives dug four-square-metre holes around the city, which they planned to fill with burning oil to reduce visibility. They also built hundreds of elaborate tunnels in the villages surrounding Mosul, rigged with explosives and booby-traps, and laid improvised explosive devices (IEDs) and mines along the roads. There was considerable concern that ISIL might employ chemical weapons against soldiers and civilians.

According to Iraqi sources, the assault towards Mosul was being waged from Al-Khazer axis (east of Mosul), Mosul Dam (northern axis), Baashiqa axis (eastern axis), Al-Qayyarah axis (southern axis) and Talul el-Baj- Al-Khadr axis (southwestern axis).

Forces involved in the offensive

About 3,000–5,000 ISIL fighters were estimated to be in Mosul city, according to the United States Department of Defense. Other estimates ranged as low as 2,000 and high as 12,000 ISIL fighters. ''Mosul Eye'' estimated approximately 8,000–9,000 fighters loyal to ISIL, with "half of them... highly trained, and the rest... either teenagers or not well trained. About ten percent of the fighters are foreign (Arabs and non-Arabs). The rest are Iraqis. Most are from Nineveh's townships and districts." Prior to the start of the battle, in late September 2016, it was estimated that around 20,000 ISIL fighters were living in Mosul, many of whom later fled the city to Syria and Ar-Raqqah, when Iraqi forces began to besiege Mosul.

The Iraqi-led coalition was initially estimated by CNN to have 94,000 members, but this number was later revised upward to 108,500; 54,000 to 60,000 Iraqi security forces (ISF) soldiers, 16,000 Popular Mobilization Forces (PMF) fighters (also referred to as PMU), and 40,000 Peshmerga (including approximately 200 Iranian Kurdish female fighters from the Kurdistan Freedom Party (PAK)) were deployed in the battle. The Iraqi and Peshmerga forces deployed for the Mosul operation were estimated to have outnumbered the ISIL militants present by 10-to-1.

Among the PMF units, the Nineveh Plain Protection Units composed of Assyrians were among the paramilitary forces in the government coalition. Shia militias, including several brigades of the paramilitary organization Hashd al-Shaabi, the Peace Companies, Kata'ib Hezbollah, the League of the Righteous, the Badr Organization, Saraya Ashura, Saraya Khorasani, Kata'ib al-Imam Ali, Harakat Hezbollah al-Nujaba and Turkmen Brigades also took part. The Ezidi community of the Sinjar region contributed the Sinjar Resistance Units (YBŞ) and Êzîdxan Women's Units (YJÊ), which operated in concert with Sunni Arab Shammar tribal militias and People's Defence Forces (HPG) of the Kurdistan Workers' Party (PKK). Other Assyrian forces involved in the planned offensive included the Nineveh Plain Forces (NPF) and Dwekh Nawsha, who are allied to the Peshmerga.

An international coalition of 60 nations, led by the United States, supported Iraq's war against ISIL, providing logistical and air support, intelligence, and advice. The international coalition forces were headquartered south of Mosul at Qayyarah Airfield West (or Q-West) in Qayyarah, which was retaken from ISIL in June. About 560 U.S. troops from the 101st Airborne Division were deployed to Q-West for the battle, including command and control elements, a security detachment, an airfield operations team, and logistics and communications specialists. The U.S. deployed HIMARS rocket launchers and M777 howitzers, manned by the 101st's 2nd Brigade Combat Team and the Golf Company, 526th Brigade Support Battalion. The British deployed several elements of the United Kingdom Special Forces as well as several L118 light guns. The French army deployed four CAESAR howitzers and 150 to 200 soldiers at Qayyarah, with 600 more French troops announced at the end of September. An additional 150 French soldiers were in Erbil, east of Mosul, training Peshmerga. The aircraft carrier '' Charles de Gaulle'', with a squadron of 24 Rafale M jets, was deployed from Toulon to the Syrian coast to support the operation against ISIL through airstrikes and reconnaissance missions; 12 other Rafale jets operated out of French Air Force bases in Jordan and the United Arab Emirates (UAE). Eighty Australian special forces soldiers and 210 Canadian Special Operations Forces Command (CANSOFCOM) soldiers were also deployed to assist the Peshmerga. In addition, the Canadian Forces 21 Electronic Warfare Regiment was also reported to be in the area, working to intercept and relay ISIL communications, while a Role 2 Canadian Army field hospital with 60 personnel was set up to treat Peshmerga casualties.

The Ba'ath loyalists group, known to be led by Saddam Hussein's former vice president Izzat Ibrahim al-Douri, issued a statement before the start of operations calling for the people of the city to start an uprising against ISIL and announced that they will fight the "terrorist organization."

The battle

October 2016: Phase One and initial advances

On 16 October 2016, Iraqi Prime Minister Haider al-Abadi declared the beginning of the assault to recapture the city of Mosul. Officials reported howitzers firing on ISIL targets later that day. The main assault began on 17 October at approximately 6a.m., local time, with shelling and the arrival of armored vehicles to the front lines. The Peshmerga in the Khazir region, east of Mosul, started the ground assault by advancing on ISIL-held villages from three fronts, while Iraqi security forces advanced from the south. Iraqi troops advanced on the Bartella area east of Mosul while ISIL fighters fired mortars at Peshmerga. The President of KRG, Massoud Barzani, said that Peshmerga and Iraqi government fighters retook from ISIL on the first day of fighting. Iraqi government officials reported inflicting severe casualties and destruction of equipment on ISIL forces in the Hamdaniya district southeast of Mosul. Wounded ISIL fighters reported to have been transferred to their de facto capital Raqqa, in Syria, for medical aid. Some ISIL fighters were reported shaving their beards and getting rid of their Afghan uniforms. Mosul's "Freedom Bridge" was destroyed in the fighting.

On 18 October, the Iraqi government declared to have captured 20 villages from ISIL within 24 hours of fighting. On the southern front, Iraqi troops retook several villages near Qayyarah, including al-Sirt, Bajwaniya, al-Hud and al-Mashraf, and parts of the al-Hamdaniya District southeast of Mosul, as well as the al-Shura District. Iraqi Federal Police also regained control of 56 oilfields in the Qayyarah district. According to reports, the Peshmerga met little resistance on the eastern front, while Iraqi and PMF fighters coming from the south faced tougher resistance from ISIL. Iraqi Army forces stormed Qaraqosh (Bakhdida), once the largest Assyrian town in Iraq, and fought with ISIL fighters who remained holed up, while also nearing Hammam al-'Alil. The Iraqi and Peshmerga advance had been slowed down during the same day due to suicide bombers, roadside IEDs and oil fires, and the allied forces were carrying out street-by-street search operations to clear out ISIL forces from the outskirts of Mosul city. The Peshmerga later paused their advance while the Iraqi Army continued its advance.

At this point in time, the Coalition strategy was reported to be to encircle Mosul completely, after which Iraqi troops would advance into the city center. As the Iraqi Army advanced on Mosul, rebellion against ISIL broke out in the city, though ISIL forces put down the revolts within a couple of days.

The Iraqi Army resumed fighting on 19 October, surrounding Qaraqosh, while ISIL deployed snipers and car bombs. Lt. Gen. Qassim al-Maliki declared that Iraqi forces had captured 13 villages north and northeast of Al Quwayr, south of Mosul, and the Iraqi Army was reported to be within of the outskirts of Mosul city. The village of Kani Harami was captured after heavy fighting in the morning with the militants retreating to Abbasiyah. A total of 22 towns were reported to have been captured, with 12 by the Peshmerga and 10 by the ISF. Nofal Hammadi, governor of the Nineveh Governorate, declared that 40% of the province had been retaken from ISIL.

The offensive to retake the town of Bashiqa northeast of Mosul was delayed due to lack of logistical support. The international coalition's commander Gary Voelsky also stated that a majority of ISIL leaders were fleeing Mosul, and predicted that foreign fighters would form the majority of militants remaining in the city.

The fighting intensified on 20 October. A large convoy of Golden Division arrived at positions retaken by the Peshmerga forces, and they also captured Bartella. According to Maj. Gen. Maan al-Saadi of the Iraqi Army, 200 ISIL fighters were killed in the fight for Bartella. The Peshmerga and NPF announced a "large-scale operation" to the north and northeast of Mosul, to retake the Assyrian towns of Tesqopa and Bashiqa. During the day, the Peshmerga captured six villages, including four on the Bashiqa front line and two on the Nawaran front, while entering another four villages. The Peshmerga briefly captured the village of Tiz Khirab but were forced to withdraw. On the southern front, Iraqi forces resumed their push north after a brief pause and recaptured six villages east of Qayyarah.

ISIL also set the Al-Mishraq sulfur plant on fire, causing two deaths and nearly 1,000 hospitalizations from sulfur fume inhalation. The group was also reported to be digging trenches to slow the advancement of coalition troops.

On 21 October, ISIL launched multiple attacks in Kirkuk to divert military resources. Multiple explosions and gun battles were reported in the city, mostly centered on a government compound, and a senior Peshmerga commander said that the attackers had entered by posing as IDPs. Meanwhile, Iraqi government forces reported that they had retaken 2 more villages south of Mosul and killed 15 militants.

On 22 October, Iraqi police declared that ISIL's attack on Kirkuk had been repelled and that all the attackers had been killed or had blown themselves up. Iraqi officials also stated that 80 people were killed in Kirkuk, primarily Kurdish security forces, and about 170 wounded; 56 ISIL militants were also killed. A reporter of Türkmeneli TV also died in the attack, while at least seven journalists were wounded. On the same day, Iraqi forces launched a large-scale offensive began to retake the Assyrian town of Bakhdida, which had remained under ISIL control after several days of fighting. Iraqi troops also advanced on the town of Tel Keppe, to the north of Mosul. On 23 October, the Peshmerga General Command also stated that the Peshmerga had cordoned off eight villages and had secured a significant stretch of the Bashiqa-Mosul highway, coming within of the city. ISIL increased its counter-attacks in order to distract the pro-government advancing towards Mosul. In addition to the attack on Kirkuk on 21 October, ISIL fighters struck Ar-Rutbah in Anbar Province, as well as Sinjar.

By 24 October, nearly 800 ISIL fighters had been killed while 78 villages were reported to have been retaken from the group. The attack on Kirkuk was also brought to an end on the same day, with 74 militants being killed and others, including the leader of the attackers, being arrested. On 25 October, Iraqi Special Operations Forces came within of the city and paused their advance to wait for reinforcements. On 26 October, Iraqi forces faced heavy resistance from ISIL as they attempted to clear the militants from villages in Shora, south of Mosul. Hundreds of ISIL suicide bombers were also reported to have been sent from Syria to defend Mosul. Meanwhile, Peshmerga forces captured the village of Derk, northeast of Mosul, where they discovered a large ISIL tunnel containing a large cache of weapons. On 27 October, the head of the United States Central Command, Gen. Joseph Votel, estimated that 800–900 ISIL militants had been killed in the battle. On 28 October, Iraqi forces recaptured the town of Al-Shura, south of Mosul, while joint Iraqi-Peshmerga forces captured Fadiliya, which lies just four kilometres away from Mosul. Meanwhile, the UN stated that ISIL had taken tens of thousands of civilians to use as human shields in Mosul, including at least 5,000 families from around Al-Shura and 2,210 families from the Nimrud area of Hamdaniya. Those who refused to go were executed.

On 29 October, the PMF launched an offensive towards the west of Mosul, with the aim of capturing the villages west of Mosul and reaching the town of Tal Afar