Excerpts from Books and Wikipedia
"Lin Tse-hsu was the strong man in Qing China. He made his name as governor-general of Hunan and Hupeh, where he destroyed massive amounts of opium. Now, the emperor gave him the task of cleaning up Canton. . . . But when a local was killed by foreign sailors and Elliot refused to hand over the culprits, Lin expelled the British, who took refuge on Hong Kong island. Fighting broke out after Lin refused to let the British buy supplies in Kowloon, and in November, British vessels clashed with the Qing navy. The first Opium War had begun. . . . Prime Minister Lord Palmerston sent in steamships and troops. It was an unequal contest, and in the 1842 Treaty of Nanking, five 'treaty ports' were opened to unrestricted foreign trade, and Britain took Hong Kong as a colony." [Furtado: 1001 Days]