People's Republic of Bulgaria

On 8 September 1946, a referendum on abolishing the monarchy and establishing a people's republic was held without observing the requirements of the Tarnovo Constitution. Bulgaria was proclaimed a people's republic on 15 September. Elections for the Sixth Grand National Assembly, tasked with drafting a new constitution, took place on 27 October. The Bulgarian Workers' Party (Communists) won, and Georgi Dimitrov headed the new government. On 10 February 1947, Bulgaria signed the Paris Peace Treaty, preserving its borders as of 1 January 1941. On 4 December 1947, the Grand National Assembly adopted the new constitution, also known as the Dimitrov Constitution. Nationalisation began in late 1947, with all property becoming state-owned. In 1948, the Communist Party's Fifth Congress formally recognised the 'dictatorship of the proletariat'. Vasil Kolarov chaired the Council of Ministers in 1949–1950 and was succeeded by Valko Chervenkov in 1950. Their rule established a totalitarian political dictatorship. Intensive socialist industrialisation and agricultural collectivisation took place in 1950–1953. The Bulgarian Patriarchate was restored on 10 May 1953, and Bulgaria joined the United Nations on 14 December 1955. At the Communist Party's April Plenum in 1956, Chervenkov was removed, and Todor Zhivkov became First Secretary of the Central Committee and later prime minister. Production grew rapidly in 1957–1970.

During the 1960s, Bulgaria's leadership sought closer ties with the Soviet Union and proposed unification, but Moscow rejected the proposal. In 1962, Anton Yugov and Valko Chervenkov were removed from office, and Zhivkov assumed key government positions. Four meetings between Zhivkov and Josip Broz Tito took place between 1963 and 1967. The country's new approach to the Macedonian question was to reveal the truth about the Macedonian population. An agreement on the emigration of Bulgarian Turks was signed in 1968. In August that year, Bulgarian troops participated in the Warsaw Pact intervention in Czechoslovakia. Drafts of a new national programme and constitution were prepared in 1968–1971.

On 16 May 1971, a referendum approved a new constitution, known as the Zhivkov Constitution. That year, the State Council adopted a new national coat of arms. In the early 1970s, agriculture was reorganised and concentrated, adversely affecting the cooperative movement. An assimilation campaign began in late 1984, changing the names of Bulgarian Muslims and Turks. It provoked resistance. In 1985, the Turkish National Liberation Movement emerged and organised a bombing at Bunovo railway station that killed seven people. In spring 1989, the situation in north-eastern Bulgaria deteriorated, and the government permitted more than 350,000 Bulgarian citizens to emigrate freely to Turkey.

In the second half of the 1980s, Mikhail Gorbachev began restructuring the Soviet political system, but no significant changes occurred in Bulgaria. Informal organisations emerged in 1988–1989. On 10 November 1989, Zhivkov was removed as General Secretary of the Bulgarian Communist Party, and on 17 November he was also removed as Chairman of the State Council. Petar Mladenov succeeded him and was later elected president of the republic.