Before World War III
Ceded to Britain at the conclusion of the Opium Wars in 1841, Hong Kong was one of the crown jewels of the British Empire in Asia.
The colony was occupied by the Empire of Japan during World War II. Following Allied victory in 1945, the colony was returned back to Britain. By that time, the Chinese Civil War had restarted. After the Communists took over the Mainland, the colony received an influx of Han Chinese refugees escaping the PRC. Hong Kong faced a possible PRC invasion during the Korean War. The United Kingdom officially recognized the People's Republic of China as legitimate government of the mainland in 1950; yet tensions between UK and the PRC continued because there were cases of PRC incursions in to Hong Kong as well as the kidnapping of Chinese refugees in the colony.
In the 1960s, the Triads remained a prominent criminal organization in Hong Kong. The Triads ran several illegal operations in the colony.
On September 1982 during Margaret Thatcher's state visit to China, Deng Xiaoping remarked that Chinese forces could easily take Hong Kong. After failing to renew Hong Kong's lease, the two countries agreed that Britain will administer Hong Kong until 1997.
World War III
Prior to the war, the Chinese government's crackdown of the Tiananmen Square Protests of 1989 was met with condemnation internationally. In Hong Kong, citizens took to the streets and protested the CPC's actions.
Initially, China was neutral during the war. Still, British Forces Overseas Hong Kong was placed on high alert. On March 1990, the United Kingdom's worst fear was confirmed when China entered the war as an ally of the Soviet Union. Chinese forces proceeded to attack allied countries and territories in the Asia-Pacific region. Hong Kong and the Portuguese colony of Macau was not spared. While Macau quickly because of the lack of Portuguese military forces, the BFOHK put up was resistance they could against the Chinese. They fought of bravely for three weeks before surrendering due to the lack of supplies and ammunition, in what is now known as the Fall of Hong Kong. This was one of the humiliating and demoralizing battles for the United Kingdom.