 According to the Yugoslav census of 1931 , the population of eastern Herzegovina comprised 4 per cent Croats , 28 per cent Muslims , and 68 per cent Serbs . According to Professor Jozo Tomasevich , the estimated population of the districts of Bileća , Gacko and Nevesinje was only around 1 @.@ 1 per cent Croat , so in those areas nearly all the NDH government appointments and local Ustaše units were staffed by Muslims , an ethnic group that made up about 23 @.@ 7 per cent of the local population . The poor Muslim peasants of eastern Herzegovina largely sided with the Ustaše . The NDH government immediately tried to strengthen their position by vilifying the Serbs , who , according to Tomasevich , comprised around 75 per cent of the population . 
 According to the Yugoslav census of 1931 , the population of eastern Herzegovina comprised 4 per cent Croats , 28 per cent Muslims , and 68 per cent Serbs . According to Professor Jozo Tomasevich , the estimated population of the districts of Bileća , Gacko and Nevesinje was only around 1 @.@ 1 per cent Croat , so in those areas nearly all the NDH government appointments and local Ustaše units <a href='uninflect' title='1'><mark>were</mark></a> staffed by Muslims , an ethnic group <a href='null_relcl' title='2'><mark>that</mark></a>made up about 23 @.@ 7 per cent of the local population . The poor Muslim peasants of eastern Herzegovina largely sided with the Ustaše . The NDH government immediately tried to strengthen their position by vilifying the Serbs , <a href='null_relcl' title='3'><mark>who</mark></a>, according to Tomasevich , comprised around 75 per cent of the population . 
According to da Yugoslav census of 1931 , tdapopulation of eastern Herzegovina comprised 4 per cent Croats , 28 per cent Muslims , and 68 per cent Serbs . According to Professor Jozo Tomasevich , the estimated population of the districts of Bileća , Gacko and Nevesinje was only around 1 @.@ 1 per cent Croat , soo in those areas nearly alll thdaDH government appointments and local Ustaše units was staffed by Muslims , an ethnic group made up bou 23 @.@ 7 per cent of the local population . The poor Muslim peasants of eastern Herzegovina largely sided with thedataše . The NDH government immediately tried to strengthen their position by vilifying the Serbs , , according to Tomasevich , comprised around 75 per cent of the population .