The communist regime in Hungary had essentially been imposed by the Soviet Union in the immediate post-war years. Although progressive measures, such as land reform, had been introduced, the regime was bureaucratic and repressive. The old right wing of Hungarian society never regarded it as legitimate.
The replacement of the authoritarian Prime Minister Mátyás Rákosi with the more progressive Imre Nagy in 1953 combined with the "de-Stalinisation" process taking place in the Soviet Union at that time had given Soviet satellite countries such as Hungary some new hope of democracy and freedom. However, despite his popularity amongst sections of the Hungarian population and despite an appeal to the UN and western governments for protection and support, Nagy was dismissed for his liberal attitude and policies.
The spontaneous, mass anti-Soviet demonstration which took place in Budapest on 23 October 1956 and lasted until 10 November had initially started as a student demonstration in central Budapest. It quickly spread to the rest of Budapest and Hungary, with tens of thousands of people taking part.
The demonstrators were calling for Imre Nagy's return to power, free elections, freedom of the press and the withdrawal of Soviet troops. What had started as a peaceful rally, however, quickly escalated into a battle between demonstrators and police.
The protests continued until the Politburo reneged on its promise to negotiate a withdrawal of Soviet forces and on 4 November decided to crush the "counter-revolution". Soviet forces invaded Budapest and other areas of Hungary, but the resistance continued for another five days. The consequences were devastating with around 3,000 Hungarians being killed and an estimated 200,000 fleeing the country as refugees.
With hindsight, the Hungarian events can be seen as one step on the road to the eventual collapse of the Soviet Union and its bloc.