Suleyman Shah
Nothing is known with certainty about Ertuğrul's life, other than that he was the father of Osman; historians are thus forced to rely upon stories written about him by the Ottomans more than a century later, which are of questionable accuracy. An undated coin, supposedly from the time of Osman, with the text "Minted by Osman son of Ertuğrul", suggests that Ertuğrul was a historical figure. Another coin reads "Osman bin Ertuğrul bin Gündüz Alp", though Ertuğrul is traditionally considered the son of Suleyman Shah.