First Opium War begins

Britain's decision to wage war on China in 1840 stemmed from a straightforward commercial problem: the Chinese imperial court refused to buy British goods at the scale London's merchants demanded. For decades, British traders had operated from the port of Canton, where they accumulated massive deficits purchasing tea, silk, and porcelain for export to Britain. To reverse this trade imbalance, British merchants began smuggling opium grown in India into China despite imperial prohibition. When Chinese official Lin Zexu seized and destroyed 20,000 chests of opium in June 1839, Britain's government saw an opening—and a provocation.

Britain dispatched a naval squadron under Commodore George Elliot to the Chinese coast in mid-1840. The British possessed overwhelming maritime advantages: steamships that outmaneuvered Chinese junks, superior gunnery, and an organized military logistics system. The campaign itself proved almost one-sided. British forces captured coastal forts, threatened the cities of Guangzhou and Shanghai, and demonstrated the futility of Chinese coastal defense. By 1841, Chinese officials began negotiating, though fighting continued intermittently through 1842.

The Treaty of Nanking, signed on August 29, 1842, formalized Britain's victory. China ceded Hong Kong to Britain in perpetuity, paid 21 million silver dollars in indemnities, and opened five treaty ports—Canton, Amoy, Foochow, Ningpo, and Shanghai—to foreign trade. The treaty also granted British citizens extraterritoriality, meaning they answered to British law rather than Chinese courts. These provisions demolished China's carefully maintained system of controlled foreign commerce and signaled the country's slide into what Chinese historians call the "century of humiliation."

The war's significance extended far beyond its immediate combatants. It established a template for Western expansion in Asia: military superiority enabling commercial domination, unequal treaties enforcing lopsided terms, and the extraction of territorial and legal concessions from weaker nations. The opium trade itself accelerated. Within decades, addiction ravaged Chinese society, creating millions of users and generating immense wealth for foreign merchants. The conflict also demonstrated that European industrial powers could impose their will on ancient civilizations through force—a lesson that shaped imperial ambitions across Asia and Africa for the next century.