Iran's 1979 Islamic Revolution replaced the Pahlavi monarchy with a theocratic republic under the doctrine of velayat-e faqih, guardianship of the Islamic jurist, which vests ultimate religious and political authority in a Supreme Leader, a position held first by Ayatollah Ruhollah Khomeini and since 1989 by Ayatollah Ali Khamenei, above the elected president and parliament.
The constitution recognizes Shia Islam as the state religion and grants limited protected status to Zoroastrian, Jewish and Christian minorities, who hold reserved parliamentary seats, while the Baha'i Faith, founded in nineteenth-century Iran and considered by its adherents a distinct post-Islamic revelation, receives no such recognition and its members face systematic persecution, including exclusion from higher education and public employment and arbitrary detention, since the government regards the Baha'i Faith as a heretical movement rather than an independent religion.
Sunni Muslims, despite comprising Iran's largest religious minority, are barred from building a Sunni mosque in Tehran and report broader restrictions in an overwhelmingly Shia state apparatus. Enforcement of religious law, including mandatory hijab requirements for women, has produced recurring mass protest, most significantly following the 2022 death in custody of Mahsa Amini.