Ertugrul was the father of Osman I, the founder of the Ottoman Empire. He was the leader of the Kay? clan of the Oghuz Turks. When arriving in Anatolia with his 400 horsemen to aid the Seljuks of Rum against the Byzantines, Ertugrul set off the chain of events that would ultimately lead to the founding of the Ottoman Empire. Like his son, Osman, and his future descendants, Ertugrul is often referred to as a Ghazi, a heroic champion fighter for the cause of Islam.
Nothing is known with certainty about Ertugrul's life, other than that he was the father of Osman. An updated coin, supposedly from the time of Osman, with the text "Minted by Osman son of Ertugrul", suggests that Ertugrul was a historical figure. Another coin reads "Osman bin Ertugrul bin Gunduz Alp", though Ertugrul is traditionally considered the son of Suleyman Shah.
Turkmenistan has issued 500 Manat silver commemorative coins to honor Ertugrul. The obverse of a coin depicts the left profile of President Saparmurat Niyazov (1991-2006). On the other hand, the reverse engraved Ertugrul Gazi.
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