Officially RUSSIAN FEDERATION, Russian ROSSIYA, or ROSSIYSKAYA FEDERATSIYA, country that stretches over a vast expanse of eastern Europe and northern Asia. Once the preeminent republic of the Union of Soviet Socialist Republics (U.S.S.R.), Russia has been an independent country since the dissolution of the union in December 1991. Under the Soviet system it was called the Russian Soviet Federated Socialist Republic (R.S.F.S.R.).

With an area of 6,592,800 square miles (17,075,400 square kilometres), Russia is the world's largest country, covering almost twice the territory of either the United States or China. It ranks sixth in the world in population, following China, India, the United States, Indonesia, and Brazil. The great majority of the people are Russians, but there also are some 70 smaller national groups living within its borders. Most of the population is concentrated in a great triangle in the western, or European, part of the country, although over the past three centuries--and particularly during the early and mid-20th century--there was a steady flow of people eastward to the Asiatic section commonly referred to as Siberia.

On its northern and eastern sides Russia is bounded by the Arctic and Pacific oceans, and it has small frontages in the northwest on the Baltic Sea at St. Petersburg and at the detached Russian oblast (province) of Kaliningrad. On the south it borders North Korea, China, Mongolia, and the former Soviet republics of Kazakstan, Azerbaijan, and Georgia. On the southwest and west it borders the former Soviet republics of Ukraine, Belarus, Latvia, and Estonia, as well as Finland and Norway; in addition, Kaliningrad (formerly a part of what was once East Prussia annexed in 1945) abuts Poland and Lithuania.

Extending nearly halfway around the Northern Hemisphere and covering much of eastern and northeastern Europe as well as the whole of northern Asia, Russia has a maximum east-west extent, along the Arctic Circle, of some 4,800 miles (7,700 kilometres) and a north-south width of 1,250 to 1,850 miles. There is an enormous variety of landforms and landscapes, which occur mainly in a series of broad latitudinal belts. Arctic deserts lie in the extreme north, giving way southward to the tundra and then to the forest zones, which cover about half of the country and give it much of its character. South of the forest zone lie the wooded steppe and steppe, beyond which are small sections of semidesert along the northern shore of the Caspian Sea. Much of the federation lies in latitudes where the winter cold is intense and where evaporation can barely keep pace with the accumulation of moisture, engendering abundant rivers, lakes, and swamps.

The capital of Russia is Moscow, which was also the capital of the R.S.F.S.R. and of the Soviet Union. The republic itself had been established immediately after the Russian Revolution of October (November, New Style) 1917 and became a union republic on Dec. 30 (Dec. 17, Old Style), 1922. Following the termination of the U.S.S.R. in 1991, Russia joined with other former Soviet republics in forming the Commonwealth of Independent States (CIS).