Austria signed the Austrian State Treaty.
Austria . In 1955 , the Austrian State Treaty re-established Austria as a sovereign state , ending the occupation . Austria also signed the Schengen Agreement in 1995 , and adopted the euro currency in 1999 . Austrian State Treaty . It was signed on 15 May 1955 in Vienna , at the Schloss Belvedere among the Allied occupying powers ( France , the United Kingdom , the United States , and the Soviet Union ) and the Austrian government .