The Ottoman Rise: From Frontier Beylik to Ankara

The Ottoman Empire began as a small beylik, a Turcoman principality founded by Osman I around 1299 in northwestern Anatolia, on the frontier with the weakened Byzantine Empire. Osman belonged to the Kayı tribe of Turcomans, part of the great migration of Turkic peoples that had moved into Anatolia after the Seljuk Sultanate of Rum fragmented in the late thirteenth century. His frontier territory drew volunteer holy warriors, or gazis, motivated by the ideal of jihad and the prospect of plunder, and Ottoman founding legend preserves the "dream of Osman," in which a great tree grew from his navel and covered the world. His son Orhan I conquered the Byzantine city of Bursa in 1326 and made it the first permanent Ottoman capital, later taking Nicaea in 1331 and Nicomedia in 1337. The crossing of the Dardanelles into Europe in 1354, through the occupation of Gallipoli, marked the start of Ottoman expansion in the Balkans.