The campaign in Mesopotamia was fought between British-led troops dominated by the Indian Army and the forces of the Ottoman Empire. In terms of the numbers engaged, it was the largest theatre of operations outside of Europe for the British Empire during the First World War.


In 1914, Mesopotamia was part of the Ottoman Empire. It was strategically important because of British oil interests in neighbouring Persia, particularly because of the importance of oil to the Royal Navy. A force was sent from India to Mesopotamia in late 1914, to secure the oil refineries at Abadan. It was designated Indian Expeditionary Force D (IEF D). Throughout the campaign, India would provide the majority of manpower and supplies.

Advance to Kut

By the end of November, IEF D had occupied the city of Basra. The small force that arrived in 1914 was reinforced considerably by the end of March 1915. Persian Arabistan was cleared of Ottoman forces during two months of heavy fighting, and the British Indian forces continued to advance further north, spurred by this early success. In November 1915, the advance was finally halted at the Battle of Ctesiphon, resulting in heavy losses. General Charles Townshend was forced to withdraw his troops to the fortified town of Kut-al-Amara. They were besieged until April 1916 to the point of near starvation.

Siege of Kut

Between January and April 1916, British and Indian troops fought up the River Tigris in an attempt to relieve the garrison at Kut. However, they failed to break through Ottoman defences and ultimately lost more men than the number under siege at Kut. When the garrison eventually surrendered in April 1916, it was perhaps the most humiliating defeat in British military history. More than 6,000 troops were captured, many of whom would be marched to prisoner of war camps across Turkey, suffering deprivation, disease and death in the process.


After the fall of Kut, British Indian forces reorganised and were put under new leadership. A renewed offensive eventually occupied Baghdad in March 1917. This was followed by a series of minor operations in the region culminating in the Battle of Sharqat. On 31 October 1918, the armistice with the Ottoman Empire came into force, ending the long campaign in Mesopotamia.

Result and Aftermath

British and Indian forces suffered casualties of more than 85,000 killed, wounded and captured in Mesopotamia. It was a campaign fought largely by the Indian Army, often in challenging conditions with limited supplies and medical care.

After the war, the Ottoman Empire was dismantled and its territories partitioned. Mesopotamia became modern day Iraq. Arabs who fought with the Allies in the hope of greater independence became disillusioned with the British Mandate in Iraq, leading to an Iraqi revolt which was subdued by the Royal Air Force in 1920.

Related Cemeteries & Memorials

Basra Memorial commemorates more than 40,620 servicemen of the British Empire who died in Mesopotamia and have no known grave. More than 33,250 of those commemorated served with the Indian Army.

Baghdad (North Gate) War Cemetery contains the graves and memorials of more than 6,880 British Empire servicemen of the First World War of whom more than 2,720 remain unidentified. Also commemorated within the cemetery are 296 Commonwealth serviceman of the Second World War along with more than 200 foreign nations and non-war graves.

Amara (Left Bank) Indian War Cemetery commemorates some 5,000 servicemen of the Indian Army, of whom only nine are identified as no comprehensive records of the burials were kept by the military authorities.