October 23 is Memorial day of the Hungarian Revolution of 1956.
Also the day of the proclamation of the Third Hungarian Republic (1989). The day is celebrated with speeches and exhibitions.
The Hungarian Revolution of 1956 or the Hungarian Uprising of 1956 was a nationwide revolt against the government of the Hungarian People’s Republic and its Soviet-imposed policies, lasting from October 23 until November 10, 1956. Though leaderless when it first began, it was the first major threat to Soviet control since the USSR’s forces drove Nazi Germany from its territory at the end of World War II.
The revolt began as a student demonstration. By the end of October, fighting had almost stopped and a sense of normality began to return.
After announcing a willingness to negotiate a withdrawal of Soviet forces, the Politburo (Political Bureau of the Central Committee of the Communist Party of the Soviet Union) changed its mind and moved to crush the revolution. On November 4, a large Soviet force invaded Budapest and other regions of the country. The Hungarian resistance continued until November 10. Over 2,500 Hungarians and 700 Soviet troops were killed in the conflict, and 200,000 Hungarians fled as refugees. By January 1957, the new Soviet-installed government had suppressed all public opposition. These Soviet actions, while strengthening control over the Eastern Bloc, alienated many Western Marxists, leading to splits and/or considerable losses of membership for communist parties in capitalist states.
Public discussion about this revolution was suppressed in Hungary for more than 30 years. Since the thaw of the 1980s, it has been a subject of intense study and debate. At the inauguration of the Third Hungarian Republic in 1989, October 23 was declared a national holiday.