The history of Macedonians has been shaped by population shifts and political developments in the southern Balkans, especially within the region of Macedonia. The ideas of separate Macedonian identity grew in significance after the First World War, both in Vardar and among the left-leaning diaspora in Bulgaria, and were endorsed by the Comintern. During the Second World War these ideas were supported by the Communist Partisans, but the decisive point in the ethnogenesis of this South Slavic people was the creation of the Socialist Republic of Macedonia after the World War II, as a new state in the framework of the Socialist Federal Republic of Yugoslavia.