History: Azerbaijan declared independence from Russia in 1918, but was incorporated in the Soviet Union in 1920. It again declared independence in August 1991, following the collapse of the USSR. The conflict between Azerbaijan and Armenia over the Nagorno-Karabakh region is still unresolved after 10 years and Baku has yet to settle disputes with its neighbors over oil rights in the Caspian Sea. During 1988-1994, Karabakh Armenians declared independence and seized almost 20 percent of the country's territory, creating an estimated 750,000 Azerbaijani refugees. As a result of the war, western Azerbaijan is plagued with landmines. Both sides have generally observed a Russian-mediated cease-fire since May 1994. Azerbaijan, with an estimated population of 8,000,000, adopted a new constitution in November 1995.