Ukraine is a large Eastern European country known for Orthodox churches and the Dnieper River. Kiev, its capital, features St. Sophia's Cathedral and the Pechersk Lavra monastery. Ukraine emerged as an independent nation in the late 20th century after being dominated by Poland-Lithuania, Russia, and the Soviet Union. It experienced brief independence after World War 1 but was later incorporated into the Soviet Union as the Ukrainian Soviet Socialist Republic. Ukraine declared sovereignty in 1990 and independence in 1991, confirmed by a popular vote.