Oman under the Ibadi clergy through the Treaty of Seeb in 1920. The last overseas possession, the port of Gwadar across the Gulf of Oman, was sold to Pakistan in 1958. However, the sultanate did gain some territory in 1967, when Britain returned the Khuriya Muriya Islands (originally granted as a gift from the sultan to Queen Victoria in 1854). Insurgency and oil drilling The discovery of oil in the Persian Gulf exacerbated the dispute between the Sultan in Muscat and the Imams of Oman. Oil exploration had begun in the early 1920s by the Anglo-Persian Oil Company. The course of the Second World War severely disrupted such activities. Further, the Sultanate of Muscat during that time was experiencing terrible social, economic and political conditions. The Sultunate was underdeveloped with no infrastructure or telephones, and Sultan Said bin Taimur prohibited anything that he considered "decadent", including radios. The British government continued to have vast political control over the Sultanate as the chief adviser to the Sultan, defense secretary and all ministers of the Sultanate except for one were British. The British government, Iraq Petroleum Company and the Sultan were keen to search for oil and made early plans (1946) to establish an army that could occupy the Imamate of Oman. The last Imam of Oman, Ghalib Bin Ali, started an uprising in 1954 when the Sultan granted licenses to the Iraq Petroleum Company despite the fact that the largest oil fields lay inside the Imamate. The hostilities were put down in 1955, but the longer conflict would evolve into the Jebel Akhdar rebellion, where Sultan Said bin Taimur relied heavily on continued British military support. Iraq Petroleum, along with its operator of oil exploration, Petroleum Development Oman, was owned by European oil giants including Anglo-Iranian Oil's successor British Petroleum which encouraged the British government to extend their support to the Sultan. The insurgency erupted again in 1957, when Saudi Arabia began supporting the Omani rebels, but eventually the Sultan was able to establish pre-eminence over most of the inland. The same year, British forces bombarded the town of Nizwa, the capital of the Imamate, and toppled the Ibadi theocracy. Ghalib Bin Ali went into exile in Saudi Arabia and the last rebel forces were defeated two years later, in 1959. The Treaty of Seeb was terminated and the autonomous Imamate of Oman abolished. The frequency of uprisings such as the