▁October , ▁under ▁the ▁leadership ▁of ▁the ▁new ▁Bulgar ian ▁pro - S ov iet ▁government , ▁the ▁Bulgar ian ▁Army ▁re enter ed ▁Y ug oslav ia ▁to ▁block ▁the ▁German ▁forces ▁in ▁their ▁withdraw al ▁from ▁Greece . ▁In ▁Mac ed onia ▁the ▁Bulg ari ans ▁fought ▁side - by - side ▁with ▁the ▁f igh ters ▁of ▁the ▁People ' s ▁Liber ation ▁Army ▁of ▁Mac ed onia . ▁ ▁V ard ar ▁Mac ed onia ▁was ▁de ▁fact o ▁liber ated ▁from ▁the ▁Germ ans ▁and ▁their ▁collaboration ists ▁in ▁late ▁November ▁ 1 9 4 4 , ▁so ▁the ▁AS N OM ▁became ▁oper ational ▁in ▁December , ▁shortly ▁after ▁the ▁German ▁retre at . ▁Nevertheless , ▁in ▁December ▁anti - comm un ist ▁Alban ian ▁national ists ▁in ▁Western ▁Mac ed onia ▁tried ▁to ▁remain ▁in ▁control ▁of ▁the ▁region ▁after ▁the ▁Y ug oslav ▁Part is ans ▁announced ▁victory . ▁They ▁aim ed ▁to ▁resist ▁incorpor ation ▁of ▁the ▁area ▁into ▁commun ist ▁Y ug oslav ia ▁and ▁it ▁was ▁only ▁in ▁early ▁ 1 9 4 5 ▁that ▁the ▁Y ug oslav ▁Part is ans ▁were ▁able ▁to ▁establish ▁their ▁control ▁over ▁the ▁mountain ous ▁area . ▁ ▁The ▁nature ▁of ▁the ▁new ▁Y ug oslav ▁state ▁remained ▁unclear ▁immediately ▁after ▁the ▁war . ▁Y ug oslav ia ▁was ▁en vision ed ▁by ▁the ▁Part is ans ▁as ▁a ▁" D em ocr atic ▁Federation ", ▁including ▁six ▁federal ▁states . ▁When ▁T ito '