Constitution Day is observed in the Northern Mariana Islands on December 8. This day commemorates the approval of the commonwealth's constitution, which was ratified by 96% of voters in a 1977 referendum and came into effect on January 9, 1978. The celebration coincides with the feast day of Our Lady of Camarin, the patron saint of the archipelago. The Northern Mariana Islands, a U.S. territory with commonwealth status, have a unique history, having been colonized by Spain, transferred to Germany, administered by Japan, and later occupied by the U.S. military during World War II. The development of the commonwealth's constitution began in 1976, and it has undergone several amendments, the most recent in 2012. As a federal territory of the United States, Congress retains the authority to alter or amend the constitution.