After the interwar kingdom was only partially successful in creation of Yugoslav nation, post-war communist authorities dismissed the idea in an effort to create federal state which will enable national emancipation of all ethnic groups. The new socialist federation enabled creation of 6 constituent republics one of which was the Socialist Republic of Macedonia. In that period Bulgarian state itself promoted identity of ethnic Macedonians in Bulgaria. Yugoslavia and Bulgaria developed close cooperation with an idea of creation of the Greater Yugoslavia and ultimately the Balkan Federation. The first formal step in that direction was made by the signing of the Bled Agreement on August 1, 1947.[3] The initiative, however, was terminated by Joseph Stalin who perceived it as a threat to his authority.[3]
Relations after 1948 Tito-Stalin split
While the Bulgarian Communist Party needed Soviet support to gain the power in the country, the League of Communists of Yugoslavia was in a position to independently establish effective control over the country already in 1945. This led new Yugoslav authorities to expect the status of an ally instead of a satellite state within the Eastern Bloc. The situation escalated in response to the 1948 Tito–Stalin split after which Yugoslav relations with all Eastern Bloc countries, including Bulgaria, were either suspended or significantly strained. Yugoslavia then reoriented its policy towards the close cooperation with Non-Aligned countries.
At the end of the 1970s and the beginning of 1980s, popular culture from Yugoslavia and particularly from the Socialist Republic of Serbia served Bulgarian citizens as a window to the West through which entertainers and other cultural content entered the country.[3]
^Bulgarian: Отношенията между България и Югославия, romanized: Otnošenijata meždu Bǎlgarija i Jugoslavija; Serbo-Croatian: Bugarsko-jugoslavenski odnosi, Бугарско-југословенски односи; Slovene: Odnosi med Bolgarijo in Jugoslavijo; Macedonian: Односите меѓу Бугарија и Југославија, romanized: Odnosite meǵu Bugarija i Jugoslavija