The distribution of Yugoslavia's major religions followed the country's internal borders only roughly. Serbia and Montenegro were under the ecclesiastical authority of the Serbian Orthodox Church. Macedonia had its own Macedonian Orthodox Church after 1967, but that republic also included many Muslim ethnic Albanians. Croatia and Slovenia were predominantly Roman Catholic, but many Orthodox Serbs also lived in Croatia, and the Muslim Slav and ethnic Albanian populations of Slovenia were growing. Bosnia and Hercegovina contained a mixture of Muslim Slavs, Orthodox Serbs, and Catholic Croats. Vojvodina had significant numbers of Eastern Orthodox, Roman Catholic, and Protestant believers; Kosovo was predominantly Muslim, although about 10 percent of the province's ethnic Albanians were Roman Catholic and virtually all its Serbs were Eastern Orthodox.
Besides Eastern Orthodoxy, Roman Catholicism, and Islam, about forty other religious groups were represented in Yugoslavia. They included the Jews, Old Catholic Church, Church of Jesus Christ of the Latter-Day Saints, Hare Krishnas, and other eastern religions. Major Protestant groups were the Calvinist Reformed Church, Evangelical Church, Baptist Church, Methodist Church, Seventh-Day Adventists, Jehovah's Witnesses, and Pentecostal Church of Christ.
The connection between religious belief and nationality posed a special threat to the postwar Communist government's official policies of national unity and a federal state structure. Although postwar constitutions provided for separation of church and state and guaranteed freedom of religion, church-state relations in the postwar period were often tense when the government attempted to reduce church influence. From 1945 to the early-1950s, the authorities carried out antichurch campaigns that imprisoned, tortured, and killed many members of the clergy. The government subsequently established a general policy of rapprochement, but until the 1980s the state still exerted pressure on many religious communities. Yugoslavs who openly practiced a religious faith often were limited to low-paying, low-status jobs. After Tito's death in 1980, the Yugoslav government no longer pursued a consistent policy toward the country's churches. After that time, each republic and province followed policies toward religion that were acceptable at home but sometimes unacceptable in other parts of the country.
Political liberalization in the late 1980s brought Yugoslavia's religious communities a level of freedom unprecedented in the postwar period. The spring of 1990 marked the beginning of a religious revival throughout the country. On Easter 1990, television stations throughout the country covered Eastern Orthodox and Roman Catholic services for the first time; two weeks later, Belgrade television broadcast prayers marking the end of Ramadan, the Muslim holy month. With the rebirth of Western-style democracy in Yugoslavia, fundamental amendments were expected in laws banning church involvement in politics, education, social and interethnic affairs, and military training.
Religious belief declined significantly in Yugoslavia after World War II, but the drop was not uniform throughout the country. In the censuses of 1921 and 1948, religious believers accounted for over 99 percent of the population. Secularization followed closely the postwar government programs of modernization, urbanization, and vigorous antireligious propaganda. A 1964 survey (Yugoslavia's last nationwide study of religion through 1990) described 70.3 percent of Yugoslavs as religious believers. The areas with the highest percentage of religious believers were Kosovo (91 percent of the population) and Bosnia and Hercegovina (83.8 percent); those with the lowest were Slovenia (65.4 percent), Serbia (63.7 percent), and Croatia (63.6 percent). Although hard figures were not available, in the late 1980s signs indicated a resurgence of religious belief, especially among young people.
Data as of December 1990