The most prominent communist leader of Bulgaria was Georgi Dimitrov, a native-born Bulgarian who had lived in exile during most of the period between the two world wars and had become a Soviet citizen in 1935. Dimitrov was prominent in the international communist movement and, while resident in Moscow, had served as secretary general of the Comintern (Communist International), founded under Lenin's guidance in 1919. Dimitrov returned to his homeland in late 1945, resumed his Bulgarian citizenship, and took over the leadership of the BKP and the government. He was instrumental in developing the 1947 Constitution (usually referred to as the Dimitrov Constitution) and set about remaking his country's economic, political, and social structures in the Soviet image. Nationalization of all means of production, collectivization of agriculture, and an ambitious program of industrialization all commenced under Dimitrov. Dimitrov died in 1949 but, before he died, his programs were well under way, the Moscow-oriented BKP was in complete control, and the country was firmly in the Soviet orbit. Several years later, even though the term _satellite_ was no longer used to describe the Eastern European countries aligned with the Soviet Union, Bulgaria was considered to be the most rigidly loyal of all former Soviet satellites. Shortly after the death of Dimitrov, the top position of leadership was secured by Vulko Chervenkov who, over the next few years, earned a reputation as Bulgaria's version of Stalin. After Stalin died, Chervenkov's power base eroded to the point that he was forced to give up the top party post in favor of Zhivkov; Chervenkov retained the top position in the government, however, and remained on the scene as an opposing locus of political power. The intraparty factional strife that ensued lasted into the 1960s, but Zhivkov, who had established a close relationship with Soviet party leader Nikita Khrushchev, eventually overcame the opposition and stabilized his regime. Zhivkov also managed to establish close relations with the Soviet leaders who ousted Khrushchev and has apparently maintained good rapport with Leonid Brezhnev, the general secretary of the Soviet party.