In 1947 he married Zsuzsanna Hölzel (1922-1998); they had six children. From 1948 onwards Hegedüs became involved with the Hungarian Working People's Party eventually taking on leading roles. From the early 1950s he took on numerous ministerial portfolios. This culminated on 18 April 1955, when he was named Prime Minister after party leader Mátyás Rákosi forced out Imre Nagy. When the Kremlin frowned on Rákosi returning to the premiership he'd held from 1952 to 1953, Hegedüs took the post. Aged 32 at the time of his appointment, he was the youngest Prime Minister in Hungarian history.