 The invasion and partition of Yugoslavia in World War II resulted in violent ethnic conflict between nationalist Serbs, Croats, Bosniaks, and others, resulting in a highly violent sectarian variant of Serbian nationalism rising in the Chetnik movement.The decentralization of the Socialist Federal Republic of Yugoslavia in the 1960s and the suppression of all ethnic nationalist sentiments led to a Serbian nationalist backlash and resurgence in the 1980s, that condemned post-World War II Yugoslavism and the decentralization of Yugoslavia.Upon Yugoslavia collapsing in the 1990s with multiple republics seeking secession, Serbian nationalists demanded that all Serbs in all the Yugoslav republics had the right to be united in a common state, ethnic conflict occurred between Serbs seeking unity with Serbia and other Yugoslav ethnicities seeking independence.