When the Kurds became Muslims, they became part of the community of the Islamic world. Kurds were then able to became a part of the political and military power of the region. When the some of largest towns in the area became part of the Rashidun Caliphate (Mosul, Erbil, Shahrizor, Seymere, Borujerd, Hamadan, Dinavar, Nahavand, Siravand, and Karaj of Abu Dulaf), they became important places of education and religion during early Islam.