During the period between the two World Wars the Balkans was a classic example of non-solved national and territorial questions, "the Macedonian question" was of the greatest significance. In Yugoslavia the Serbs were in preponderance with 40% of the total population, while Macedonians, Croats, Slovenes etc. were the rest of the population. Over 1.000.000 Macedonians, Turks and others lived in Greece; 16% of the population in Bulgaria were from Macedonian and Turkish origin.

After 1919 the national question was treated by the Comintern in accordance with the communist ideology and the state interests of the USSR - once in favour of the revisionist states (1919 - 1941), another time in favour of the anti-fascist states (1941 - 1943).

The Communist parties on the Balkans set and solved the Macedonian national question within the frames of the Comintern policy. Three periods are distinguished in the history of the communist parties of Yugoslavia (KPJ), Bulgaria (BKP) and Greece (KPG): 1. The period "neither statehood nor nationality" for the Macedonian people (1918 - 1924); 2. The period of "statehood without nationality"(1924 - 1935); 3. The period of "nationality without statehood" (after 1931 and 1945). During the first period, the Balkan Communist parties didn’t recognize the existence of the Macedonian nation and its right for union. They advocated the preservation of the territorial integrity of the kingdom of SHS (Serbs, Croats and Slovenes), Bulgaria and Greece and the partition of Macedonia within the frames of the above-mentioned states. During the second period, under the influnce of the Comintern, the Balkan Communist Parties advocated the establishment of "the united and independent Macedonia" on the Balkans, but still they didn’t recognize the existence of the Macedonian nation.

During the third period, the Balkan parties, under the influence and pressure of the Macedonian people, rejected the attitude that the Macedonian people are diversity of nations and recognized the Macedonian nation considering different historical periods. However, they didn’t recognize the right of the Macedonian people to unite its partitioned fatherland and didn’t expect the establishment of an independent Macedonian national state on the Balkans.

KPJ made an important step concerning the Macedonian national question. Its policy evoluted towards the policy of KPG and BKP. It accepted the principle policy of "nationality and statehood" concerning the Macedonian people and the other peoples in the prospective Yugoslav federation.

The recognition of the Macedonian nation by the Balkan Communist parties was a result of the continous historical pressure exerted by the Macedonian people concerning both - the recognition of the Macedonian national individuality and the Macedonian language. Metodiya Shatorov-Sharlo, Vasil Ivanovski, Pavel Shatev, Dimitar Vlahov, Kocho Ratsin etc. performed the most important part concerning the defense and affirmation of the Macedonian national and political interests during the period between the two World Wars.