Europe is one of the seven continents of Earth, taking up 3,930,000 square miles (2% of Earth and 6.8% of its land area). The continent is the world's second-smallest continent after Oceania, and Russia takes up 39% of the continent, also having the largest population. Europe has a population of 752,452,000, 11% of the world population, with its native inhabitants being primarily of Indo-European descent with a large minority of Uralic (Estonian, Hungarian, Finnish, etc.) and Turkic (Tatar, Bashkirs, Chuvash, Crimean Tatar etc.), and some other groups. Europe was the birthplace of Western civilization, seeing the civilizations of Ancient Greece and Ancient Rome, the Classical Era, the Middle Ages, being the dominant civilization on the planet during the Renaissance, Baroque, Enlightenment, the Industrial Revolution and the world wars, until its influence declined during the Cold War and the Information Age. Today, a large amount of the continent is united under the European Union, which has a common currency (the Euro), citizenship, and borders.