The Anatolian beylik of Germiyan with its capital in Kütahya is one of the prominent frontier principalities established by Oghuz Turkish clans after the decline of Seljuq Sultanate of Rûm.

According to Agoston and Masters, Germiyanoğulları were Turkmens who had immigrated to the west because of Mongol pressure in the second half of the thirteenth century.