Dual Monarchy: A system where two separate kingdoms are ruled by the same monarch, follow the same foreign policy, exist in a customs union with each other and have a combined military but are otherwise self-governing.
Compromise of 1867: An agreement that established the dual monarchy of Austria-Hungary. It gave Hungary more autonomy and recognized it as an equal partner in the empire to placate Hungarian nationalist demands.
Franz Joseph I: He was Emperor of Austria, King of Hungary, Croatia, and Bohemia from December 1848 until his death on November 21, 1916. During his reign he agreed to Compromise of 1867 which resulted in establishment of Dual Monarchy.