Sayyed Abol-Ghasem Mostafavi-Kashani ( Persian : سید ابوالقاسم کاشانی Abu’l-Qāsem Kāšāni ; 19 November 1882 – 13 March 1962) was an Iranian politician and Shia Marja . He played an important role in the 1953 coup in Iran and the overthrow of Prime Minister Mohammad Mosaddegh .