The United Arab Emirates (UAE), or simply the Emirates, consists of seven emirates and was founded on December 2, 1971 as a federation, after UK armed forces left the region. Six of the seven emirates (Abu Dhabi, Dubai, Sharjah, Ajman, Umm Al Quwain and Fujairah) declared their union on December 2, 1971. The seventh, Ras al Khaimah, joined the federation on February 10, 1972. The seven sheikdoms were formerly known as the Trucial States, in reference to the truce treaties established with the British in the 19th century.