Dündar Bey
Uncle of Ottoman Sultan, Osman I

Dündar Bey was the youngest son of the Kayı Bey Suleyman Shah or Gündüz Alp and the younger brother of Ertuğrul (13th century). He was the uncle of Osman I, the founder of the Ottoman Empire.
Biography
At the time of the division of the Kayı tribe, Dündar Bey migrated with his older brother Ertuğrul after the death of their father. When Ertuğrul died c. 1280, the leadership/chief beyship of the Kayı tribe transferred to Ertuğrul's son, Osman I. When Osman I decided to attack a small Greek island, Dündar set a trap for him; Dündar rebelled because he thought such an attack would destroy the tribe. The circumstances surrounding his death are, like many other details of his ill-documented life, disputed. Historical sources disagree on whether or not he was executed by Osman I.
In popular culture
Dündar Bey has been portrayed in Turkish television series; Kuruluş "Osmancık" (1988), Diriliş: Ertuğrul (2014—2019) and Kuruluş: Osman (2019—2021).
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This entry incorporates text from “Dündar Bey” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.