The communists promised the Croatian and other peoples that after the war they would have their states in a federative Yugoslavia. To be sure, a federative Yugoslavia composed of six republics was pro- claimed, but the national question was not solved. Instead of a democracy, a dictatorship of a narrow group led by Tito was established. The army, police and diplomatic corps were dominated by Serbs and Montenegrans, while many Croatian communists were removed or liquidated.
All democratic decisions were suspended, the Catholic church was persecuted and the Croatian archbishop and cardinal, Alojzije Stepinac, was sentenced to life imprisonment. As the most economically developed republics, Croatia and Slovenia were exploited to Serbia's advantage. The use of the pure Croatian language was prohibited as well as all equality among nations. As a result, in 1971 a wave of dissatisfaction appeared among the Croatian people, and demands for a Croatian state, federalization, alteration of the constitution and other items were directed at Belgrade.
This was the so-called Croatian Spring, which was forcefully crushed at the end of 1971, as thousands of Croats were imprisoned, killed or forced 'into emigration. Tito was compelled to permit a Serbian majority in the government and the army, but in 1974 he instituted a Constitution by which each republic is considered a state with its own borders. It was through the establishment of these borders in 1945 that Croatia was finally left without Srijem and Boka kotorska, which were ceded to Vojvodina and Montenegro, respectively. After Tito's death (1980), the internal break-up of Yugoslavia commenced.
In 1986, the Serbian Academy of Arts and Sciences renewed the Greater Serbia program (with their "Memorandum") already drafted in the Nacertanije ("Outline") in the nineteenth century, which called for the unification of all Serbs throughout Yugoslavia into one state. When Slobodan Milosevic became the secretary of the Serbian Communist Party in 1987, the implementation of this program began in earnest.