Shahidullah Kaiser was active in politics and cultural movements from his student days. Following the formation of Pakistan in 1947, he joined the provincial Communist Party of East Pakistan. He started working as a journalist in 1949 with the Ittefaq in Dhaka. In 1952, he participated actively in the Language Movement. In 1958, Kaiser joined as an associate editor of the Daily Sangbad – a Bangla language daily where he worked for the rest of his life. When the Military coup of 1958 put Ayub Khan in power, and martial law was proclaimed, Kaiser was arrested again on 14 October 1958 and remained in jail for four years till his release in September 1962.
Disappearance
Kaiser was rounded up on December 14, 1971. He never returned, nor was his body ever found. It is assumed that he was executed along with other intellectuals. His brother, Zahir Raihan, a notable film-maker, also disappeared while searching for Kaiser.