Europe (pronounced /ˈjɜrəp/, /ˈjʊərəp/) is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural River, the Caspian Sea, and by the Caucasus Mountains to the southeast. Europe is washed upon to the north by the Arctic Ocean and other bodies of water, to the west by the Atlantic Ocean, to the south by the Mediterranean Sea, and to the southeast by the Black Sea and the waterways connecting it to the Mediterranean. Yet the borders for Europe—a concept dating back to classical antiquity—are somewhat arbitrary, as the term continent can refer to a cultural and political distinction or a physiographic one.
Europe is the world's second-smallest continent by surface area, covering about 10,180,000 square kilometres (3,930,000 sq mi) or 2% of the Earth's surface and about 6.8% of its land area. Of Europe's approximately 50 states, Russia is the largest by both area and population, while the Vatican City is the smallest. Europe is the third most populous continent after Asia and Africa, with a population of 731 million or about 11% of the world's population; however, according to the United Nations (medium estimate), Europe's share may fall to about 7% in 2050.
Europe, in particular Ancient Greece, is often considered to be the birthplace of Western culture. It played a predominant role in global affairs from the 16th century onwards, especially after the beginning of colonialism. Between the 17th and 20th centuries, European nations controlled at various times the Americas, most of Africa, Oceania, and large portions of Asia. Both World Wars were ignited in Central Europe, greatly contributing to a decline in European dominance in world affairs by the mid-20th century as the United States and Soviet Union took prominence. During the Cold War Europe was divided along the Iron Curtain between NATO in the West and the Warsaw Pact in the East. 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.