Mohammad Kazem Khorasani or Akhund-e Khorasani (Persian: محمد کاظم خراسانی, (1839-1911)) was Twelver Shi'a Marja, politician, philosopher, reformer born in Mashhad. He's regarded as one of the most important Shia Mujtahid at the time. He was a lecturer at Najaf seminary for years and significant number of students from "different regions of the Muslim world" used to participate his lectures. His most famous work is The Sufficiency (Arabic: کفایه) where he gathered the jurispurdential ideas such as `continuity` and "presented them in a yet more rigorous fashion as a unified theory of jurisprudence." He is known for using his position as a marja for political use in the Persian Constitutional Revolution (1905-1911) where he was one of the main clerical supporters of the revolution. He believed that "constitutional form of government" would be the best possible choice in the absence of Imam and regarded the "Persian revolution" a Jihad ("holy war") in which all Muslims had to participate. He died "suddenly" and "mysteriously", when he aimed to leave Iraq for Iran in order against support constitutionalists' resistance to the Anglo-Russian invasion in 1911.