Macau Special Administrative Region Establishment (SARE) Day (known as 'Dia Commemorativo do Estabelecimento da Região Administrativa Especial de Macau' in Portuguese) is celebrated on 20 December and commemorates the Chinese government assuming formal sovereignty over Macau on 20 December 1999.
Macau first became a major settlement and trading post with the arrival of the Portuguese in the 16th century.
In 1557, the Portuguese established a permanent settlement in Macau, paying an annual rent of Silver to the Chinese. Up to 1863, the Portuguese continued to pay an annual tribute to stay in Macau.
Following the Carnation Revolution of 1974 in Portugal, the new Portuguese government decided it would relinquish all its overseas possessions. In 1976, Lisbon redefined Macau as a "Chinese territory under Portuguese administration" and granted it a large measure of administrative, financial, and economic autonomy.
In June 1986, the Chinese and Portuguese governments commenced negotiations on the sovereignty of Macau. The two countries signed a Joint Declaration in 1987, making Macau a special administrative region (SAR) of China. The Chinese government assumed formal sovereignty over Macau on 20 December 1999.
Since the change in sovereignty, Macau's economy has continued to prosper benefiting from the growth of tourism from mainland China and the construction of new casinos