First Opium War

Series of military engagements of 1839-1842 between the British Empire and Qing China, triggered by China's enforcement of its opium ban through the seizure of British merchants' opium stocks at Guangzhou under Lin Zexu. The Royal Navy's technologically superior ships and weapons defeated China, which signed the Treaty of Nanking on 29 August 1842 - the first of the 'unequal treaties' - paying an indemnity, opening five treaty ports, granting extraterritoriality, and ceding Hong Kong Island. The war began what Chinese nationalists call the century of humiliation and started 156 years of British rule in Hong Kong.