Iranian Kurdistan or Eastern Kurdistan (Kurdish: Rojhilatê Kurdistanê ڕۆژهەڵاتی کوردستان), is an unofficial name for the parts of northwestern Iran inhabited by Kurds which borders Iraq and Turkey. It includes Kurdistan Province, Kermanshah Province, Hamadan Province most of Ilam Province, and some parts of West Azerbaijan and North Khorasan provinces.
Kurds generally consider northwestern Iran (Eastern Kurdistan) to be one of the four parts of a Greater Kurdistan, which also includes parts of southeastern Turkey (Northern Kurdistan), northern Syria (Rojava or Western Kurdistan), and northern Iraq (Southern Kurdistan).
According to the last census conducted in 2006, the four Kurdish-inhabited provinces in Iran, West Azerbaijan (2,873,459), Kermanshah Province (1,879,385), Kurdistan Province (1,440,156), and Ilam Province (545,787) have a total population of 6,738,787.
From the 4 to 5 million Iranian Kurds, a majority are Sunni Muslims.Sunni Muslim Kurds inhabit Kurdistan province and some parts of Kermanshah and West Azerbajani province. Shia Kurds inhabit Kermanshah Province, except for those parts where people are Jaff, and Ilam Province; as well as some parts of Kurdistan and Hamadan provinces. The Kurds of Khorasan Province in northeastern Iran are also adherents of Shia Islam. During the Islamic revolution in Iran the major Kurdish political parties were unsuccessful in absorbing Shia Kurds, who have not been politically active or demonstrated interest in autonomy or independence.