Waves of mass migrations from Hong Kong villagers exercised their right of abode in the United Kingdom and left for Europe. In 1967, a series of large-scale riots erupted in Hong Kong, causing social instability. These events led some of the richer Hong Kong residents to move abroad. Emigration took place to countries in Southeast Asia, South Africa or South American countries. This wave did not come to a rest until the mid-1970s. On the 19th of December 1984, the People's Republic of China and the United Kingdom signed the "Sino-British Joint Declaration", validated the 1997 transfer of sovereignty over Hong Kong to China. The declaration prompted
British Hong Kong the Chinese, the Second Convention of Peking was signed on 9 June. Since the foreign powers had agreed by the late 19th century that it was no longer permissible to acquire outright sovereignty over any parcel of Chinese territory, and in keeping with the other territorial cessions China made to Russia, Germany and France that same year, the extension of Hong Kong took the form of a 99-year lease. The lease consisted of the rest of Kowloon south of the Shenzhen River and 230 islands, which became known as the New Territories. The British formally took possession on 16 April