He was Secretary-General during the crucial period 1943–1949 when the Polish United People’s Party was being formed. Gomułka’s attempted defiance of Stalinism led to his dismissal and imprisonment (1951). He was restored to power (1956) on the intervention of Khrushchev, after Polish and Soviet frontier troops had exchanged fire in the wake of serious rioting in Poznań. He helped to sustain a degree of post-Stalinist liberalism, but resigned in 1970 following popular disturbances against increases in food prices.