Common law, a free port, hard money, and a press that printed what it found — built by refugees in two generations, guaranteed by treaty to last fifty years past 1997. It lasted twenty-three.
Hong Kong Island was ceded to Britain in 1841 at the close of the First Opium War. Kowloon followed in 1860. The much larger New Territories were added in 1898 under a 99-year lease — a lease date that ended up fixing the handover a century later almost to the year.
The Communist victory on the mainland in 1949 sent waves of refugees into Hong Kong, roughly doubling its population within a few years. Many arrived with nothing but family networks and trade skills. The textile, garment and plastics industries they built through the 1950s and 1960s turned a colonial port into an export economy.
Facing a currency crisis ahead of the handover negotiations, Hong Kong's monetary authority pegged the Hong Kong dollar to the US dollar at a fixed rate in October 1983. The peg has held, with only minor band adjustments, for four decades.
Britain and China signed the Joint Declaration on 19 December 1984, agreeing that Hong Kong would return to Chinese sovereignty in 1997 and that its common-law courts, free port, and civil liberties would continue unchanged for fifty years under a "one country, two systems" framework, registered with the United Nations as a binding treaty.
Hong Kong reverted to Chinese sovereignty at midnight on 1 July 1997. Its Basic Law, drafted to implement the Joint Declaration, preserved the common-law judiciary, the Hong Kong dollar, and a press that continued to print stories the mainland press could not.
A proposed law allowing extradition to the mainland triggered the largest protests in Hong Kong's history, with organizers estimating turnout above a million people on multiple occasions. The bill was withdrawn in October, but the protests continued into 2020.
China's National People's Congress Standing Committee imposed a National Security Law directly on Hong Kong, bypassing the territory's own Legislative Council — twenty-seven years before the fifty-year clock set in 1984 was due to run out.
23 of 50 years — how far into the Joint Declaration's guarantee Hong Kong had run when the National Security Law arrived.
The American statutory response, and what changed because of it, is recorded in full under American support.