Mesopotamian campaign
The Mesopotamian campaign or Mesopotamian front[9] was a campaign in the Middle Eastern theatre of World War I fought between the Allies represented by the British Empire, troops from Britain, Australia and the vast majority from British Raj, against the Central Powers, mostly the Ottoman Empire. It started after British amphibious landings in 1914 which sought to protect Anglo-Persian oil fields in Khuzestan and the Shatt al-Arab. However, the front later evolved into a larger campaign that sought to capture the key city of Baghdad and divert Ottoman forces from other fronts. It ended with the Armistice of Mudros in 1918, leading to the cession of Iraq (then Mesopotamia) and further partition of the Ottoman Empire.
Fighting began after an amphibious landing by an Anglo-Indian division at the fortress of Al-Faw before rapidly advancing to the city of Basra to secure British oil fields in nearby Persia (now Iran). Following the landings, Allied forces won a string of victories along the Tigris and Euphrates Rivers, including repulsing an Ottoman attempt to retake Basra at the Battle of Shaiba. The advance stalled when the Allies reached the town of Kut south of the city of Baghdad in December 1915. At Kut, the Allied army was besieged and destroyed, later dubbed "the worst defeat of the Allies in World War I".[10] Following this defeat, the Allied army reorganized and began a new campaign to take Baghdad. Despite fierce Ottoman resistance, Baghdad was captured in March 1917 and the Ottomans suffered more defeats until the Armistice at Mudros.
The campaign ended with a British mandate over Mesopotamia being established and change of the power balance following the Ottoman expulsion from the region. In Turkey, elements of the last Ottoman parliament still claimed parts of modern-day Iraq such as Mosul as being Turkish, leading to Allied occupation of Constantinople. The British mandate over Mesopotamia later failed as a large-scale Iraqi revolt fueled by discontent with the British administration took place in 1920, leading to the Cairo Conference in 1921. There, it was decided a Hashemite kingdom under heavy British influence would be established in the region with Faisal as its first monarch.
On 30 October 1918, the Armistice of Mudros was signed and both parties accepted their current positions. General Marshall accepted the surrender of Khalil Pasha and the Ottoman 6th Army on the same day, but Cobbe did not hold his current position as the armistice required, and continued to advance on Mosul in the face of Turkish protests.[45] British troops marched unopposed into the city on the 14 November 1918. The ownership of Mosul Province and its rich oil fields became an international issue.
The war in Mesopotamia was over on 14 November 1918. It was 15 days after the Armistice and one day after the occupation of Constantinople.
The British Empire forces suffered 85,197 battle casualties in Mesopotamia. There were also 820,418 hospitalisations for non-battle causes, mostly sickness. Of those, 16,712 died, 634,889 were treated and put back on duty in-theater, and 154,343 were permanently evacuated from the theatre. Those evacuated accounted for some 18.8% of total non-battle casualties, while those who died were 2%. By comparison, 49% of those wounded in battle (26,814 men) were evacuated, and 8.9% (5,281) died.[47] Thousands more died out of theatre from injuries and sickness incurred here, or died in Ottoman captivity. Total British military deaths in the Mesopotamian Campaign, including from the latter causes, were 38,842 (1,434 officers and 37,408 men),[48] including 28,578 from sickness and other non-battle causes (including prisoners). The unusually high ratio of non-battle to battle casualties in Mesopotamia, and the unusually high incidence of permanent losses among non-battle casualties had much to do with the geography of the area of operations. It was unhygienic, extremely hot in the summer, extremely cold in the winter, composed primarily of either sandy deserts or marshes, and was underdeveloped, meaning men had to be transported large distances for medical attention.[49]
The Ottomans suffered 325,000 casualties on the Mesopotamian Campaign.[8] Deaths from disease were double the Ottoman deaths in battle in the First World War and greater than this in Mesopotamia.[50] Ottoman irrecoverable battle casualties totalled 55,858 (13,069 KIA, 22,385 WIA, 20,404 POW). They were divided up as follows:[51]
The WIA figures only include irrecoverable losses (crippled or died of wounds). Going by Erickson's estimates, the total of wounded outnumbered seriously wounded by 2.5:1 for the war.[50] Applying that same ratio to the Mesopotamia Campaign produces a total battle casualty count of about 89,500 (13,069 KIA, 56,000 WIA, 20,404 POW). By the end of 1918 the British had deployed 350,000–410,000 men into the theatre, 112,000 of them front-line troops. The vast majority of the British empire forces in this campaign were recruited from India.