Austria-Hungary was a dual monarchy in Central Europe that existed from 1867 to 1918. It was formed by the union of the Austrian Empire and the Kingdom of Hungary, each having its own government but sharing a common monarch. The empire was diverse, comprising various ethnic groups, including Germans, Hungarians, Slavs, and Italians. The empire played a significant role in European politics and was a major player in World War I. Its complex political structure and ethnic tensions contributed to its eventual dissolution after the war, leading to the creation of several independent nations, including Czechoslovakia and Yugoslavia.