One of the provinces in Iran, Kordestan is the only province in historical Kurdistan that bears this name, which means "land of the Kurds." However, Kordestan covers only part of the historical Kurdish area in Iran. Kurds also live in Kirmanshah, Western Azerbaijan, Ilam, and Hamadin.
Sanandaj (Sinna) is the capital of Kordestan and the general name of the district around it. The population is largely Sunni Kurdish. Sheikhs of the Naqshbandi sufi order have traditionally been influential, although earlier the mirs of Ardalan were Shiite, possibly because of their former connections to the Ahl-i Haqq. Most Kurds in the region speak the so-called southeastern dialects of Kurdish, which are closer to modern Persian than Sorani. Just to the west, however, there are Gurani speakers.
Historical Dictionary of the Kurds. Michael M. Gunter.