Rise of the Ottoman Empire
The foundation and rise of the Ottoman Empire is a period of history that started with the emergence of the Ottoman principality in , and ended with the conquest of Constantinople on May 29, 1453. This period witnessed the foundation of a political entity ruled by the Ottoman Dynasty in the northwestern Anatolian region of Bithynia, and its transformation from a small principality on the Byzantine frontier into an empire spanning the Balkans and Anatolia. For this reason, this period in the empire's history has been described as the Proto-Imperial Era. Throughout most of this period, the Ottomans were merely one of many competing states in the region, and relied upon the support of local warlords and vassals to maintain control over their realm. By the middle of the fifteenth century the Ottoman sultans were able to accumulate enough personal power and authority to establish a centralized imperial state, a process which was brought to fruition by Sultan Mehmed II (r. 1451-1481). The conquest of Constantinople in 1453 is seen as the symbolic moment when the emerging Ottoman state shifted from a mere principality into an empire, marking a major turning point in its history.
History of the Ottoman Empire
In the century after the death of Osman I, Ottoman rule began to extend over the Eastern Mediterranean and the Balkans. Osman's son, Orhan, captured the city of Bursa in 1326 and made it the new capital of the Ottoman state. The fall of Bursa meant the loss of Byzantine control over Northwestern Anatolia. The important city of Thessaloniki was captured from the Venetians in 1387. The Ottoman victory at Kosovo in 1389 effectively marked the end of Serbian power in the region, paving the way for Ottoman expansion into Europe. The Battle of Nicopolis in 1396, widely regarded as the last large-scale crusade of the Middle Ages, failed to stop the advance of the victorious Ottoman Turks. With the extension of Turkish dominion into the Balkans, the strategic conquest of Constantinople became a crucial objective. The Empire controlled nearly all former Byzantine lands surrounding the city, but the Byzantines were temporarily relieved when Timur invaded Anatolia in the Battle of Ankara in 1402. He took Sultan Bayezid I as a prisoner. The capture of Bayezid I threw the Turks into disorder. The state fell into a civil war that lasted from 1402 to 1413, as Bayezid's sons fought over succession. It ended when Mehmed I emerged as the sultan and restored Ottoman power, bringing an end to the Interregnum.