Most of the UK's Caribbean territories achieved independence after the departure in 1961 and 1962 of Jamaica and Trinidad from the West Indies Federation, established in 1958 in an attempt to unite the British Caribbean colonies under one government, but which collapsed following the loss of its two largest members. Barbados achieved independence in 1966 and the remainder of the eastern Caribbean islands in the 1970s and 1980s, but Anguilla and the Turks and Caicos Islands opted to revert to British rule after they had already started on the path to independence. The British Virgin Islands, Cayman Islands and Montserrat opted to retain ties with Britain, while Guyana achieved independence in 1966. Britain's last colony on the American mainland, British Honduras, became a self-governing colony in 1964 and was renamed Belize in 1973, achieving full independence in 1981. A dispute with Guatemala over claims to Belize was left unresolved.