Background: Once the center of power for the large Austro-Hungarian Empire, Austria was reduced to a small republic after its defeat in World War I. Following annexation by Nazi Germany in 1938 and subsequent occupation by the victorious Allies, Austria's 1955 State Treaty declared the country "permanently neutral" as a condition of Soviet military withdrawal. Neutrality, once ingrained as part of the Austrian cultural identity, has been called into question since the Soviet collapse and Austria's increasingly prominent role in European affairs. A prosperous country, Austria joined the European Union in 1995 and the euro monetary system in 1999.