<P> The Treaty of Nanking , the Supplementary Treaty of the Bogue , and two French and American agreements were all `` unequal treaties '' signed between 1842 and 1844 . The terms of these treaties undermined China 's traditional mechanisms of foreign relations and methods of controlled trade . Five ports were opened for trade , gunboats , and foreign residence : Guangzhou , Xiamen , Fuzhou , Ningbo , and Shanghai . Hong Kong was seized by the British to become a free and open port . Tariffs were abolished thus preventing the Chinese from raising future duties to protect domestic industries and extraterritorial practices exempted Westerners from Chinese law . This made them subject to their own civil and criminal laws of their home country . Most importantly , the opium problem was never addressed and after the treaty was signed opium addiction doubled . China was forced to pay 21 million silver taels as an indemnity , which was used to pay compensation for the traders ' opium destroyed by Commissioner Lin . A couple of years after the treaties were signed internal rebellion began to threaten foreign trade . Due to the Qing government 's inability to control collection of taxes on imported goods , the British government convinced the Manchu court to allow Westerners to partake in government official affairs . By the 1850s the Chinese Maritime Customs Service , one of the most important bureaucracies in the Manchu Government , was partially staffed and managed by Western Foreigners . In 1858 opium was legalised , and would remain a problem . </P>
<P> The Treaty of Nanking , the Supplementary Treaty of the Bogue , and two French and American agreements were all `` unequal treaties '' signed between 1842 and 1844 . The terms of these treaties undermined China 's traditional mechanisms of foreign relations and methods of controlled trade . Five ports were opened for trade , gunboats , and foreign residence : Guangzhou , Xiamen , Fuzhou , Ningbo , and Shanghai . Hong Kong was seized by the British to become a free and open port . Tariffs were abolished thus preventing the Chinese from raising future duties to protect domestic industries and extraterritorial practices exempted Westerners from Chinese law . This made them subject to their own civil and criminal laws of their home country . Most importantly , the opium problem was never addressed and after the treaty was signed opium addiction doubled . China was forced to pay 21 million silver taels as an indemnity , which was used to pay compensation for the traders ' opium destroyed by Commissioner Lin . A couple of years after the treaties were signed internal rebellion began to threaten foreign trade . Due to the Qing government 's inability to control collection of taxes on imported goods , the British government convinced the Manchu court to allow Westerners to partake in government official affairs . By the 1850s the Chinese Maritime Customs Service , one of the most important bureaucracies in the Manchu Government , was partially staffed and managed by Western Foreigners . In 1858 opium was legalised , and would remain a problem . </P>
what commodity ultimately led to british gaining control of hong kong in the treaty of nanjing
what commodity ultimately led to british gaining control of hong kong in the treaty of nanjing
opium
opium