Osman I or as he is known, Osman Gazi or Osman Bey.(; 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. Wikipedia