The Mesopotamian campaign or Mesopotamian front (Turkish: Irak Cephesi) was a campaign in the Middle Eastern theatre of World War I fought between the British Empire, with troops from Britain, Australia and the vast majority from the British Raj, and the Central Powers, primarily the Ottoman Empire, over control of Ottoman Iraq. It started after the British Fao Landing in 1914, which sought to protect Anglo-Persian Oil Company oil fields in Khuzestan province and the Shatt al-Arab waterway. The front later evolved into a larger campaign that sought to capture the 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 and further partition of the Ottoman Empire.
The British advanced from Al-Faw to the city of Basra to secure British oil fields in nearby Iran. Following the landings, British forces won a string of victories along the Tigris and Euphrates rivers, including the repulse of an Ottoman attempt to retake Basra at the Battle of Shaiba. The advance stalled when the British reached the town of Kut, south of the city of Baghdad in December 1915. The Siege of Kut led to the defeat of the British force, later called "the worst defeat of the Allies in World War I". The British re-organised 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 a change of the balance of power following the Ottoman expulsion from the region. In Turkey, elements of the Misak-ı Millî, the last Ottoman parliament, still claimed parts of modern Iraq such as Mosul as being Turkish, leading to Allied occupation of Constantinople. The British mandate over Mesopotamia later failed as an Iraqi revolt in 1920, caused by discontent with the British administration, led to the Cairo Conference in 1921. It was decided a Hashemite kingdom under British influence would be established in the region with Faisal as its first monarch.
Background
Prior to Ottoman entry into World War I, the British had gained exclusive rights to oil fields in south-western Persia (modern Iran), many in Arabistan, under the jurisdiction of the Anglo-Persian Oil Company. Persia had previously been divided by the British and Russian Empires into spheres of influence in 1907, with these oil fields under British influence. The oil pipeline to transport the Persian petroleum ran alongside the Karun River into the Shatt al-Arab waterway, with refineries based on Abadan Island in the area. Much of the Shatt al-Arab also flowed through Ottoman-owned Mesopotamia, making this pipeline vulnerable to invasion.
The petroleum in this region was vital for Britain's new oil-fired, turbine based dreadnoughts as well as toluol for the production of explosives. Britain wanted to retain its dominance of the Persian Gulf, show support for local Arabs, and demonstrate power to the Ottomans, with Sir Edmund Barrow, military secretary to the Indian Office, stating, "ostensibly to protect the oil installation but in reality to notify the Turks that we mean business and to the Arabs that we are ready to support them". Growing German influence in the region caused by the creation of the Berlin–Baghdad railway was of concern to London. As for the Turks, they were unable fully to control Iraq and constantly engaged in border disputes with neighbouring Persia. Local policy was largely decided by local Arab tribes.
Later on 14 November 1914, the Ottoman government declared a holy war, dubbed the jihad ("struggle"), against enemies of Islam with the exception of the Central Powers, which swayed some Ottoman Arabs to stay loyal to the empire and fight the Allied Powers. This notably included some Shia Muslims, a previously oppressed group within the empire. A 1912 agreement between the Indian and British military offices stated that in the event of war in the Persian Gulf or Mesopotamia, it would be the responsibility of the Indian military to mount a campaign in the region. However, the Gulf was not a priority to London as the Suez Canal and Western Front were seen as more important, whereas Delhi planned an offensive campaign to take Baghdad. On 29 October 1914, Ottoman warships commanded by the German admiral Wilhelm Souchon, bombarded several Russian Black Sea ports, prompting a Russian declaration of war on 2 November 1914, with Britain and France following suit on 5 November.
With the Ottoman Empire now at war with the principal allied powers, its priorities included the Caucasus Campaign against Russia, with the Ottoman war minister, Enver Pasha sending the 37th Division and XIII Corps Headquarters to this theatre in support of the Third Army. The entire XII Corps was deployed to the Sinai and Palestine Campaign. Fourth Army Headquarters was sent to Syria, to replace the Second Army Headquarters, which was sent to Istanbul. In place of the Fourth Army was the "Iraq Area Command" with only the 38th Division under its command. This division was led by Lt.Col. Süleyman Askeri Bey. British operational planning included landing troops in the Shatt-al-Arab and mount a largely defensive campaign. The reinforced 6th (Poona) Division of the British Indian Army was assigned the task, designated as Indian Expeditionary Force D (IEFD) and stationed in Bahrain in anticipation of invasion. The Allies originally planned to seize Persian-controlled Abadan Island, but fear of provoking a war with Persia led to planned landings at Fao instead.
Operations
1914
On 6 November 1914, British offensive action began with the naval bombardment of the old fort at Fao, located at the point where the Shatt-al-Arab meets the Persian Gulf. At the Fao Landing, the British Indian Expeditionary Force D (IEF D), comprising the 6th (Poona) Division led by Lieutenant General Arthur Barrett with Sir Percy Cox as Political Officer, was opposed by 350 Ottoman troops and 4 guns. After a short engagement, the fort was overrun, killing many enemy troops. By mid-November the Poona Division was fully ashore and began moving towards the city of Basra.
The same month, the ruler of Kuwait, Sheikh Mubarak Al-Sabah, contributed to the Allied war effort by sending forces to attack Ottoman troops at Umm Qasr, Safwan, Bubiyan, and Basra. In exchange the British government recognised Kuwait as an "independent government under British protection." There is no report on the exact size and nature of Mubarak's attack, though Ottoman forces did retreat from those positions weeks later. Mubarak soon removed the Ottoman symbol from the Kuwaiti flag and replaced it with "Kuwait" written in Arabic script. Mubarak's participation and previous exploits in obstructing the completion of the Baghdad railway helped the British safeguard the Persian Gulf by preventing Ottoman and German reinforcement.
On 22 November, the British occupied the city of Basra after a short fight with soldiers of the Iraq Area Command under Suphi Bey, the Governor of Basra. The Ottoman troops abandoned Basra and retreated up the river. After establishing order in the town the English forces continued their advance, and at the Battle of Qurna they succeeded in capturing Subhi Bey and 1,000 troops. This put the British in a very strong position, ensuring that Basra and the oilfields would be protected from any Ottoman advance. The main Ottoman army, under the command of Khalil Pasha, was 275 mi (443 km) to the north-west around Baghdad that made only weak efforts to dislodge the British.
1915
On 2 January, Süleyman Askerî Bey took over as head of the Iraq Area Command. With Gallipoli, the Caucasus, and Palestine taking priority, the Ottoman Army had few resources to move to Mesopotamia. Süleyman Askerî Bey sent letters to Arab sheiks in an attempt to organise them to fight against the British. He wanted to retake the Shatt-al-Arab region at any cost.
Early on the morning of 12 April, Süleyman Askerî attacked the British camp at Shaiba in what became known as the Battle of Shaiba. He had about 4,000 regular troops and about 14,000 Arab irregulars provided by Arab sheiks. Although the irregulars proved ineffective, the Ottoman infantry launched a series of relentless attacks on the fortified British camp and later attempted by bypass it. When the British cavalry and infantry counterattacked the defensive forces Suleyman Askari pulled his troops back. The next day the British attacked his defensive positions. It was a hard-fought infantry battle in which the British infantry overcame tough Ottoman opposition. Ottoman losses numbered 2400 men killed, wounded, or taken prisoner, as well as two artillery field pieces. The retreat ended 75 miles (120 kilometres) up the river at Hamisiye. Süleyman Askerî had been wounded at Shaiba. Disappointed and depressed, he shot himself at the hospital in Baghdad. In his place Colonel Nureddin was appointed commander of the Iraq Area Command on 20 April 1915. Nureddin was one of the few officers to reach high command without the benefit of a staff college education. He did, however, have extensive combat experience.
Due to the unexpected success British command reconsidered their plan and General Sir John Nixon was sent in April 1915 to take command. He ordered Charles Vere Ferrers Townshend to advance to Kut or even to Baghdad if possible. Townshend and his small army advanced up the Tigris river. They defeated several Ottoman forces sent to halt him. In July 1915, a force led by G. F. Gorringe captured the city of Nasiriyah, capturing the Turks' largest supply depot in southern Mesopotamia. Although his advance was very difficult to sustain logistically, it was maintained.
In late September 1915, amidst the recent defeat of Serbia and entry of Bulgaria into the war and concerns about German attempts to incite jihad in Persia and Afghanistan, Grey (Foreign Secretary) and other politicians encouraged a further 100-mile (160-kilometre) push to Baghdad. The CIGS Murray thought this logistically unwise, but Kitchener advised the Dardanelles Committee (21 October) that Baghdad be seized for the sake of prestige, then abandoned.
Enver Pasha worried about the possible fall of Baghdad. He realised the mistake of underestimating the importance of the Mesopotamian campaign. He ordered the 35th Division and Mehmet Fazıl Pasha to return to Mosul, their old location. The 38th Division was reconstituted. The Sixth Army was created on 5 October 1915, and its commander was a 72-year-old German general, Colmar von der Goltz. Von der Goltz was a famous military historian who had written several classic books on military operations. He had also spent many years working as a military adviser in the Ottoman Empire. However, he was in Thrace commanding the Ottoman First Army and would not reach the theatre for some time. Colonel Nureddin the former commander of the Iraq Area Command was still in charge on the ground.
On 22 November, Townshend and Nureddin fought a battle at Ctesiphon, a town 25 miles (40 kilometres) south of Baghdad. The conflict lasted five days. The battle was a stalemate as both the Ottomans and the British ended up retreating from the battlefield. Townshend concluded that a full scale retreat was necessary. However, Nureddin realised the British were retreating and cancelled his retreat, then followed the British. Townshend withdrew his division in good order back to Kut-al-Amara. He halted and fortified the position. Nureddin pursued with his forces. He tried to encircle the British with his XVIII Corps composed of the 45th Division, 51st Division and 2nd Tribal Cavalry Brigade. The exhausted and depleted British force was urged back to the defences of Kut-al-Amara. The retreat finalised on 3 December. Nureddin encircled the British at Kut-al-Amara, and sent other forces down river to prevent the British from marching to the relief of the garrison.
The Mesopotamian Half Flight from Australia was formed in 1915 to give air support. On 7 December, the siege of Kut began. From the Ottoman perspective the siege prevented the Sixth Army from performing other operations. From the British perspective defending Kut, as opposed to retreating back to Basra, was a mistake since Kut was isolated. It could be defended, but it could not be resupplied. Von der Goltz helped the Ottoman forces build defensive positions around Kut. The Sixth Army was reorganised into two corps, the XIII and the XVIII. Nureddin Pasha gave command to Von der Goltz. With the reorganisation, the Sixth Army laid siege to the British. New fortified positions established down river fended off any attempt to rescue Townshend. Townshend suggested an attempt to break out, but this was initially rejected by Sir John Nixon; however he relented. Nixon established a relief force under the command of General Fenton Aylmer. Aylmer made three major attempts to break the siege, but each effort was unsuccessful.
1916
On 20 January, Enver Pasha replaced Nureddin Pasha with Colonel Halil Kut (Khalil Pasha). Nureddin Pasha did not want to work with a German general. He sent a telegram to the War Ministry "The Iraq Army has already proven that it does not need the military knowledge of Goltz Pasha ..." After the first failure, General Nixon was replaced by General Lake. British forces received small quantities of supplies from the air. These drops were not enough to feed the garrison, though. Halil Kut forced the British to choose between starving and surrendering, though in the meantime they would try to lift the siege.