In 1917-18 Britain invaded Palestine and was granted a mandate under the League of Nations. Britain, however, had contradictory obligations to Arabs and Jews. The British had attempted to give Arab leaders the impression that their support during the war would be rewarded by independence in some form, when in fact the Balfour Declaration of 1917 promised to support Jewish claims for a 'National Home' in Palestine.
With increasing Jewish immigration in the mid-1920s the situation was fraught and Jewish settlements were being attacked. The 1930 Passfield report highlighted Arab grievances and recommended curbing Jewish immigration, which the British government rejected.
Following an Arab rebellion in 1936, Earl Peel oversaw a Royal Commission that recommended partition into separate Arab and Jewish states; the Peel report was published in July 1937. Given the approach of war and the need to protect oil sources, Britain changed approach to soothe Arab opinion. A 1939 White Paper explicitly rejected a Jewish state and restricted immigration.
International opinion swung in favour of a separate Jewish state after the revelation of the holocaust. The Labour Foreign Secretary, Ernest Bevin, attempted to negotiate a unitary state in which Britain played a part, but was continually frustrated. Violence increased and in 1946 the Irgun (The National Military Organization in the Land of Israel) blew up the Royal David Hotel, which housed the British administration. In September 1947, Bevin renounced the mandate and British troops withdrew the following year. Partition was then carried out under the United Nations.
Britain occupied Mesopotamia during the First World War and obtained a mandate. Bound by the 1922 October Treaty, Britain was to negotiate the creation of a national Iraqi government that agreed to British military demands. The British achieved an Anglo-Iraqi military treaty in 1927, which enabled the British to use Iraqi airfields for military purposes. The mandate ended in 1932, when Iraq became fully independent. Britain temporarily occupied Iraq during the Second World War and overpowered a rebellion in 1941. The Anglo-Iraqi Treaty was reaffirmed in 1949 in spite of opposition to the partition of Palestine.
Britain was determined to hold on to Cyprus and, in the late 1950s, was engaged in a major counter-insurgency campaign to suppress a rebellion by Greek-Cypriots guerrillas seeking union with Greece.