War flag of Austria-Hungary (1918).svg

The Austro-Hungarian Empire consisted of two monarchies (Austria and Hungary) and was one of the Central Powers in World War I. Austia-Hungary initiated the war in 1914 after declaring war on Serbia forcing its ally Russia to intervene. This in turn, led to other nations also participating through treaty obligations. It was de facto dissolved by the time the military authorities signed an armistice at Villa Giusti on 3 November 1918.