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.
Islam in Europe
The Ottoman Empire began its expansion into Europe by taking the European portions of the Byzantine Empire in the 14th and 15th centuries up until the 1453 capture of Constantinople, establishing Islam as the state religion in the region. The Ottoman Empire continued to stretch northwards, taking Hungary in the 16th century, and reaching as far north as the Podolia in the mid-17th century (Peace of Buczacz), by which time most of the Balkans was under Ottoman control. Ottoman expansion in Europe ended with their defeat in the Great Turkish War. In the Treaty of Karlowitz (1699), the Ottoman Empire lost most of its conquests in Central Europe. The Crimean Khanate was later annexed by Russia in 1783. Over the centuries, the Ottoman Empire gradually lost almost all of its European territories, until its collapse in 1922, when the former empire was transformed into the nation of Turkey.