The Iran–Iraq War began on 22 September 1980, when Iraq invaded Iran, and ended on 20 August 1988, when Iran accepted the UN-brokered ceasefire. Iraq wanted to replace Iran as the dominant Persian Gulf state, and was worried that the 1979 Iranian Revolution would lead Iraq's Shi'ite majority to rebel against the Ba'athist government. The war also followed a long history of border disputes, and Iraq planned to annex the oil-rich Khuzestan Province and the east bank of the Arvand Rud (Shatt al-Arab).