Ukraine is a country in Eastern Europe. It borders Russia to the northeast, Belarus to the north, Poland, Slovakia and Hungary to the west, Romania and Moldova to the southwest and the Black Sea to the south. The historic city of Kiev (Kyiv) is the republic's capital.
From at least the ninth century the territory of present-day Ukraine was a key centre of medieval East Slavic civilization that formed the state that became known as Kievan Rus and for the following several centuries the territory was divided between a number of regional powers. After a brief period of independence (1917-1921) following the Russian Revolution of 1917, Ukraine became one of the founding Soviet Republics in 1922. The Ukrainian Soviet Socialist Republic's territory was enlarged westward after the Second World War and finally in 1954 with the Crimea transfer. Ukraine became independent again after the Soviet Union's collapse in 1991.