Rákosi was born in Ada, a village in Bács-Bodrog County in the Kingdom of Hungary (now a town in Vojvodina, Serbia). Born to Jewish parents, the fourth son of József Rosenfeld, a grocer, his mother Cecília Léderer would give birth to seven more children. Of his younger siblings the most notable was Ferenc Rákosi (later Biró, 1904–2006), an administrator, who also became active in Communist politics and was, for a time, General Manager of the Mátyás Rákosi Steel and Metal Works during his brother's rule. His other siblings were Béla (1886–1944), Jolán (1888–?), Matild Gizella (1890–?), Izabella (1895–?), Margit (1896–1932), Zoltán (1898–?), Mária (1902–1938), Dezső (1906–?) and Hajnal (1908–1944).