Azerbaijan is a landlocked country in the South Caucasus region of Eurasia. The country is bounded by the Caspian Sea to the east, Russia to the north, Georgia to the northwest, Armenia to the west and Iran to the south. Azerbaijan has a complex history that has often been at the crossroads of powerful empires. In the late 19th century, the Russian Empire controlled Azerbaijan. However, in 1918, Azerbaijan declared its independence, becoming one of the first Muslim-majority countries to do so. The country was annexed by the Soviet Union in 1920 and regained its independence in 1991. Azerbaijan is a member of the United Nations, the Council of Europe, the Organization for Security and Cooperation in Europe (OSCE), and the Cooperation Council for the Arab States of the Gulf.