Ertugrul (Ottoman Turkish: ارطغرل‎, Turkish: Ertuğrul Gazi, Erṭoġrıl; often with the title Gazi) (died c. 1280) was the father of Osman I, the founder of the Ottoman Empire. While his historicity is proven by coins minted by Osman I which identify Ertuğrul as the name of his father, nothing else is known for certain about his life or activities. According to Ottoman tradition, he was the son of Suleyman Shah, leader of the Kayı tribe of Oghuz...

Seljuk, also spelled Seljuq, ruling military family of the Oğuz (Ghuzz) Turkic tribes that invaded southwestern Asia in the 11th century and eventually founded an empire that included Mesopotamia, Syria, Palestine, and most of Iran. Their advance marked the beginning of Turkish power in the Middle East. Although individual Turkish generals had already gained considerable, and at times decisive, power in Mesopotamia and Egypt during the tenth...