Macau Special Administrative Region Establishment Day is observed in Macau every December 20 to commemorate the transition of Macau from a Portuguese colony to a special administrative division of the People's Republic of China. This holiday marks the culmination of a long process that began after World War II when dissatisfaction with Portuguese governance grew. Following the overthrow of the Portuguese dictatorship in 1974, Portugal decided to relinquish its overseas possessions, leading to the signing of the Sino-Portuguese Joint Declaration in 1987, which established the framework for Macau's return to China. The declaration officially took effect on December 20, 1999. The day is significant for recognizing Macau's unique status and history, and it is celebrated with various observances throughout the region.