The Treaty of Versailles, which ended World War I, led to the decline of Germany as a major European power. Like many Germans of the period, Hitler, who had fought in the German Army but still held Austrian citizenship at the time, believed the treaty to be a betrayal, with the country having been "stabbed in the back" by its own government, particularly as the German Army was popularly thought to have been undefeated in the field. For the defeat, Hitler scapegoated civilian leaders and Marxists, later called the "November Criminals".