The British Mandate for Mesopotamia (Arabic: الانتداب البريطاني على العراق) was a Mandate proposed to be entrusted to Britain at the San Remo, Italy-based conference, in accordance with the Sykes–Picot Agreement.
The proposed mandate was awarded on April 25, 1920, at the San Remo conference in Italy, but was not yet documented or defined. It was to be a Class A mandate under Article 22 of the Covenant of the League of Nations. A draft mandate document was prepared by the British Colonial Office in June 1920. The Mandate with British administration was enacted via the Anglo-Iraqi Treaty.
The proposed mandate faced certain difficulties to be established, as a nationwide Iraqi revolt broke out in 1920, after which it was decided the territory would become the Kingdom of Iraq, via the Anglo-Iraq Treaty. The Kingdom of Iraq became independent in 1931-1932, in accordance with the League of Nations stance, which stated such states would be facilitated into progressive development as fully independent states.
The civil government of postwar Iraq was headed originally by the High Commissioner, Sir Percy Cox, and his deputy, Colonel Arnold Wilson. British reprisals after the murder of a British officer in Najaf failed to restore order. British administration had yet to be established in the mountains of north Iraq. The most striking problem facing the British was the growing anger of the nationalists, who felt betrayed at being accorded mandate status.
Map presented by TE Lawrence to the Eastern Committee of the War Cabinet in November 1918