The Anatolian beylik of Germiyan with its capital in Kütahya was one of the prominent frontier principalities established by the Oghuz Turks 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 13th century.

For a brief period in the second half of the 14th century, Germiyan Dynasty was second only to Karamanid Dynasty in its rising power. But they were later taken over by the neighboring Osmanoğlu dynasty, who were to found the Ottoman Empire later.

Germiyans played a crucial role in settling Turkish populations along the coastal regions of the Aegean Sea, the founders of the Beyliks of Aydin, Sarukhan, İnançoğlu and Menteşe having started out as Germiyan commanders.

Because of various factors arising from the Mongol invasion, their branch of the clan had left the regions of Fars and Kirman, and headed west into Anatolia, having remained for a time around Malatya, and then moving to the Kütahya area, where their beylik was formed rather rapidly.

They rebelled against the central power in 1283, upon the execution of the sultan Kaykhusraw III by the Mongols, and placing of Mesud II on the Seljuq throne. The struggle between combined Mongol-Seljuq forces based in Konya and the rebel forces of Germiyan continued until 1290. An agreement could only be reached in 1299, upon which the Germiyan Dynasty also entered into possession of Ankara. When the Ilkhanid governor Emir Çoban took over Anatolia in 1314, they declared allegiance and concentrated on raids towards the regions to their west.

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