Ottoman beylik in the context of "Bithynia"

Anatolian beyliks (Turkish: Anadolu beylikleri, Ottoman Turkish: Tavâif-i mülûk, Beylik; Turkish pronunciation: [bejlic]) were Turkish principalities (or petty kingdoms) in Anatolia governed by beys, the first of which were founded at the end of the 11th century. A second and more extensive period of establishment took place as a result of the decline of the Seljuq Sultanate of Rûm in the latter half of the 13th century.

One of the beyliks, the ottoman beylik that of the Osmanoğlu of the Kayı branch of Oghuz Turks, from its capital in Bursa completed its incorporation of the other beyliks to form the Ottoman Empire by the late 15th century.

Osman I or as he is known, Osman Gazi or Osman Bey.(Ottoman Turkish: عثمان غازى , عثمان بك, romanized: ʿOsmān Ġāzī; Turkish: I. Osman or Osman Gazi; died 1323/4) was the eponymous founder of the Ottoman Empire (first known as a beylik or emirate). While initially a small Turkoman principality during Osman's lifetime, his beylik transformed into a vast empire in the centuries after his death. It existed until 1922 shortly after the end of World War I, when the sultanate was abolished.

Owing to the scarcity of historical sources dating from his lifetime, very little factual information about Osman has survived. Not a single written source survives from Osman's reign, and the Ottomans did not record the history of his life until the fifteenth century, more than a hundred years after his death. Because of this, historians find it very challenging to differentiate between fact and myth in the many stories told about him. One historian has even gone so far as to declare it impossible, describing the period of Osman's life as a "black hole".

Osman I or Osman Ghazi (Ottoman Turkish: عثمان غازى, romanized: ʿOsmān Ġāzī; Turkish: I. Osman or Osman Gazi; died 1323/4) was the eponymous founder of the Ottoman Empire (first known as a beylik or emirate). While initially a small Turkoman principality during Osman's lifetime, his beylik transformed into a vast empire in the centuries after his death. It existed until 1922 shortly after the end of World War I, when the sultanate was abolished.

Owing to the scarcity of historical sources dating from his lifetime, very little factual information about Osman has survived. Not a single written source survives from Osman's reign, and the Ottomans did not record the history of his life until the fifteenth century, more than a hundred years after his death. Because of this, historians find it very challenging to differentiate between fact and myth in the many stories told about him. One historian has even gone so far as to declare it impossible, describing the period of Osman's life as a "black hole".