Austria was under occupation until 1945.
Austria . In 1955 , the Austrian State Treaty re-established Austria as a sovereign state , ending the occupation . `` Austria -- the Nazis ' first victim '' -- a political slogan declared on the Moscow Conference in 1943 that became the ideological basis of Austria and national self-consciousness of Austrians during the periods of allied occupation of 1945-1955 and sovereign state of the Second Austrian Republic ( 1955 -- 1980s ) . The 1955 Austrian State Treaty ended the four-power occupation and recognized Austria as an independent and sovereign state .