Sheikh Mujibur Rahman was the apparent acting president of a state yet to be known as Bangladesh (during the Liberation war of Bangladesh, when it was still called East Pakistan, before he was captured, taken to West Pakistan, and kept in a Pakistani prison. His imprisonment therefore resulted in his absence during the entire war-time, which lasted almost a year. In his absence, Syed Nazrul Islam, vice-president of the Provisional Government of Bangladesh was appointed as acting president). Sheikh Mujibur Rahman was the founder of Bangladesh and remarked as the 'Father of the Bangladesh Nation'. He headed the Awami League, served as the president from April 1971 to 1972; was the prime minister from 1972 and the president in 1975. He is popularly referred to as Sheikh Mujib, and with the honorary title of Bangabandhu (বঙ্গবন্ধু Bôngobondhu, "Friend of Bengal"). His eldest daughter Sheikh Hasina Wajed is the present leader of the Awami League and the current prime minister of Bangladesh. He introduced the state policy of Bangladesh according to four basic principles: nationalism, secularism, democracy and socialism.