The Ottoman Empire, historically also known as the Turkish Empire, was a state that spanned much of Southeast Europe, West Asia, and North Africa from the 14th century to the early 20th century, centered around modern-day Turkey. It also controlled parts of southeastern Central Europe between the early 16th and early 18th centuries. The empire emerged from a beylik, or principality, founded in northwestern Anatolia in c. 1299 by the Turkoman tribal leader Osman I. His successors conquered much of Anatolia and expanded into the Balkans by the mid-14th century, transforming their petty kingdom into a transcontinental empire. The Ottomans ended the Byzantine Empire with the conquest of Constantinople in 1453 by Mehmed II. Further conquests by Selim I lead the Sultans to adopt the title of caliph. With its capital at Constantinople and control over a significant portion of the Mediterranean Basin, the Ottoman Empire was at the centre of interactions between the Middle East and Europe for six centuries. Ruling over so many peoples, the empire granted varying levels of autonomy to its many confessional communities, or millets, to manage their own affairs per Islamic law. During the reign of Suleiman the Magnificent in the 16th century, the Ottoman Empire became a global power. Modern academic consensus posits that the empire began to decline after defeat in the Second Siege of Vienna in 1683, but continued to maintain a flexible and strong economy, society and military into much of the 18th century. The Ottoman Empire fell behind technologically from the rest of Europe by the 18th century as imperial authority fragmented. Further defeats from Austria and Russia culminated in the loss of territory, and with rising nationalism after the French Revolution, a number of new states emerged in the Balkans.