The siege of Kut Al Amara, also known as the first battle of Kut, was the besieging of an 8,000 strong British Army garrison in the town of Kut, 160 km (100 mi) south of Baghdad, by the Ottoman Army. In 1915, its population was around 6,500. Following the surrender of the garrison on 29 April 1916, the survivors of the siege were marched to imprisonment at Aleppo, during which many died. Historian Christopher Catherwood has called the siege "the worst defeat of the Allies in World War I". Ten months later, the British Indian Army, consisting almost entirely of newly recruited troops from Western India, conquered Kut, Baghdad and other regions in between in the Fall of Baghdad.

The fall of Baghdad occurred during the Mesopotamia Campaign, fought between the forces of the British Empire and the Ottoman Empire in the First World War.