In 1991, in the last census taken in Yugoslavia, Bosnia had a population of 4,364,574. In 1998, after Bosnia’s civil war, which left hundreds of thousands dead and forced many thousands of others to flee, the United States government estimated that Bosnia’s population was 3,365,727. Casualty rates during the war were approximately equal for the ethnic Muslims and Serbs (between 1992 and 1995, 7.4 percent of the prewar Muslim population and 7.1 percent of the prewar Serb population were killed or listed as missing); the casualty rate for the ethnic Croats was much lower. Of the Bosnians who fled, most went to the FRY, Germany, Croatia, and Sweden.

The country is home to members of numerous ethnic groups. The three largest are the Bosniacs, Serbs, and Croats, who constitute about two-fifths, one-third, and one-fifth, respectively, of the population. Physically the three groups are indistinguishable; culturally the major difference between them is that of religious origin and affiliation. Serbs belong to the Serbian Orthodox tradition, Croats to the Roman Catholic, and Bosniacs to the Islamic. The association of religion with national identity has meant that, in spite of low attendance at church and mosque services, religious identity has remained important. The demise of communism has brought religious revival within all three populations, partly in response to the end of official disapproval and partly in assertion of national identity.