Operation Parthenon was a British plan for military intervention in Zanzibar following the 1964 revolution. The operation was authorised by the British Commanders Committee East Africa on 30 January. The main objectives were to restore law and order in Zanzibar and to prevent the radical left-wing Umma Party from taking control of the government from the moderate Afro-Shirazi Party. The forces assigned to the operation included two aircraft carriers, three destroyers, a Royal Fleet Auxiliary vessel, 13 helicopters, 21 transport or reconnaissance aircraft, a battalion of Foot Guards, a battalion of Royal Marines and an independent company of paratroopers. The plan was to launch a helicopter and parachute assault of Unguja, Zanzibar's main island, before proceeding to take the smaller island