British Mandate of Palestine
The British Mandate of Palestine was a short-lived British possession that occupied Israel and Jordan from the end of World War I until around 1948. A similar French mandate existed in Syria and Lebanon around the same time.
Ostensibly set up as a mandate of the League of Nations, the British exercised political and military control over the region for close to thirty years.
Although it enhanced security of the Suez Canal and the route to India, the British found the area difficult to control due to conflict between Jews and Arabs. In the face of increasing expenses and manpower requirements, the British chose to give both Jordan and Israel their independence and to leave the area.