Europe is one of the traditional seven political continents, and a peninsular sub-continent of the geographic continent Eurasia. Europe is bounded to the north by the Arctic Ocean, to the west by the Atlantic Ocean, to the south by theMediterranean Sea, and to the southeast by the Caucasus Mountains, the Black Sea and the waterways connecting the Black Sea to the Mediterranean. To the east, Europe is generally divided from Asia by the water divide of the Ural Mountains, the Ural River, and by the Caspian Sea. Europe is sometimes referred to as a "penninsula of penninsulas".
Europe covers approximately 10,180,000 square kilometres (3,930,000 sq mi) or 2% of the Earth's surface and about 6.8% of the planet's total land area. It hosts around fifty sovereign states, the precise number depending on the underlying definition of Europe's border, as well as on the inclusion or exclusion of states which are not fully recognized internationally. Europe contains both Russia, the world's largest country by area and Europe's largest by population, as well as the Vatican, the smallest on both counts (not counting the non-sovereign Pitcairn Islands in the Pacific). Europe is the third most populous continent after Asia and Africa with a population of 731,000,000 or about 11% of the world's population. According to UN population projection (medium variant), Europe's share will fall to 7% in 2050, numbering 653 million. However, Europe's borders and population are in dispute, as the term continent can refer to a cultural and political distinction or aphysiographic one.
Europe is the birthplace of Western culture. European nations played a predominant role in global affairs from the 16th century onwards, especially after the beginning of colonization. By the 17th and 18th centuries European nations controlled most of Africa,the Americas, and large portions of Asia. World War I and World War II led to a decline in European dominance in world affairs as the United States and Soviet Union took prominence. The Cold War between those two superpowers divided Europe along the Iron Curtain. European integration led to the formation of the Council of Europe and the European Union in Western Europe, both of which have been expanding eastward since the fall of the Soviet Union in 1991.