The December Constitution (German: Dezemberverfassung) is a set of six acts that served as the constitution of the Cisleithanian half of Austria-Hungary. The acts were proclaimed by Emperor Franz Joseph on 21 December 1867 and functioned as the supreme law of the land until the collapse of the empire in 1918. Five of the Constitution's acts were replaced by the Federal Constitutional Law between 1918 and 1920; the sixth law, a bill of rights, is still in force.