Why Did China Lease Hong Kong to Britain?

Bird's eye view of Hong Kong by Mee Fong Studios, c. 1900-1923
Hong Kong Harbor, taken sometime between 1900 and 1923, during British control of the island. Library of Congress Prints and Photos

The short answer to that question is that China lost Hong Kong to Great Britain in the Opium Wars and later leased adjacent territories to the British under duress. Britain's reign over Hong Kong dates back to the 1842 Treaty of Nanking, which ended the First Opium War.

The Longer Answer to Why Britain Took Over Hong Kong

Nineteenth-century Britain had an insatiable appetite for Chinese tea, but the Qing Dynasty and its subjects did not want to buy anything that the British produced.

The government of Queen Victoria did not want to use up any more of the country's reserves of gold or silver to buy tea, so it decided to forcibly export opium from the Indian subcontinent to China. The opium would then be exchanged for tea.

China's government, not too surprisingly, objected to the large-scale importation of narcotics into their country by a foreign power. When just banning opium imports did not work—because British merchants simply smuggled the drug into China—the Qing government took more direct action. In 1839, Chinese officials destroyed 20,000 bales of opium. This move provoked Britain to declare war in order to protect its illegal drug-smuggling operations.

The First Opium War lasted from 1839 to 1842. Britain occupied the island of Hong Kong on January 25, 1841, and used it as a military staging point. China lost the war and had to cede Hong Kong to Britain in the aforementioned Treaty of Nanking.

Hong Kong became a crown colony of the British Empire.

Status Changes of Hong Kong, Kowloon, and the New Territories

At this point, you may be wondering, "Wait a minute, Britain just grabbed Hong Kong. Where did the lease come in?"

The British grew increasingly worried about the security of their free port at Hong Kong during the second half of the 19th century.

It was an isolated island, surrounded by areas still under Chinese control. The British decided to make their authority over the area official with a legally binding lease. 

In 1860, at the end of the Second Opium War, the United Kingdom gained a perpetual lease over the Kowloon Peninsula, which is the mainland Chinese area just across the strait from Hong Kong Island. This agreement was part of the Convention of Beijing, which ended that conflict.

In 1898, the British and Chinese governments signed the Second Convention of Peking, which included a 99-year lease agreement for the islands surrounding Hong Kong, called the "New Territories."  The lease awarded control of more than 200 surrounding small islands to the British. In return, China got a promise that the islands would be returned to it after 99 years.

On December 19, 1984, British Prime Minister Margaret Thatcher and Chinese Premier Zhao Ziyang signed the Sino-British Joint Declaration, in which Britain agreed to return not only the New Territories but also Kowloon and Hong Kong itself when the lease term expired. China promised to implement a "one country, two systems" regime, under which for 50 years Hong Kong citizens could continue to practice capitalism and political freedoms forbidden on the mainland.

So, on July 1, 1997, the lease ended and the government of Great Britain transferred control of Hong Kong and surrounding territories to the People's Republic of China.  The transition has been more or less smooth, although human rights issues and Beijing's desire for greater political control cause considerable friction from time to time.