The Qizilbash, Anatolian adherents to the Safavid order, held a strong presence across Anatolia from the late 15th century to the mid-16th century and assumed a central role in the Şahkulu rebellion. In the decades preceding the events of the rebellion, due to the fluid religious character of the region, the primarily Sunni Ottoman state demonstrated a notable tolerance towards Shia Islam. However, beginning in the early 16th century, this tolerance began to recede; according to official Ottoman terminology from the period, a Qizilbash was a rebel heretic suspected of illicit relationships with the Safavids. Some ascribe this receding tolerance to the decline of the Aq Qoyunlu coupled with the emerging socio-political legitimacy of the Safavid empire.
