Grand Ayatollah Hussein-Ali Montazeri (24 September 1922 – 19 December 2009; , ) was an Iranian Shia Islamic theologian, Islamic democracy advocate, writer and human rights activist. He was one of the leaders of the Iranian Revolution and one the highest-ranking authorities in Shīʿite Islam. In 1979, he became a former designated successor to the revolution's Supreme Leader Ayatollah Khomeini, with whom he had a falling-out in 1989 over government policies that Montazeri claimed infringed on people's freedom and denied them their rights. Montazeri spent his later years in Qom and remained politically influential in Iran, but was placed in house arrest in 1997 for questioning "the unaccountable rule exercised by the supreme leader." He was known as the most knowledgeable senior Islamic scholar in Iran and a "grand marja" (religious authority) of Shia Islam.