Ukraine (i// yew-KRAYN; Ukrainian: Україна; transliterated: Ukrayina; [ukrɑˈjinɑ]) is a country in Central and Eastern Europe. Ukraine borders the Russian Federation to the east and northeast, Belarus to the northwest, Poland, Slovakia and Hungary to the west, Romania and Moldova to the southwest, and the Black Sea and Sea of Azov to the south and southeast, respectively. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after the Russian Federation.
From at least the ninth century, the territory of Ukraine was a 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 when the Soviet Union dissolved in 1991.
Ukraine is a unitary state composed of 27 regions: 24 oblasts (provinces), one autonomous republic (Crimea), and two cities with special status: Kiev, its capital and largest city, and Sevastopol, which houses the Russian Black Sea Fleet under a leasing agreement. Ukraine is a republic under a semi-presidential system with separate legislative, executive, and judicial branches. Since the dissolution of the Soviet Union, Ukraine continues to maintain the second largest military in Europe, after that of Russia. The country is home to 46 million people, 77.8 percent of whom are ethnic Ukrainians, with sizable minorities of Russians (17%), Belarusians and Romanians. The Ukrainian language is the official language in Ukraine. Russian is also widely spoken. The dominant religion in the country is Eastern Orthodox Christianity, which has heavily influenced Ukrainian architecture, literature and music.