Handover of Hong Kong
The United Kingdom controlled many parts of India by the 1830s. Their goal in this land was to grow cotton so that they didn't have to buy so much from the United States. They were not able to grow cotton, but they found out that they could grow poppies in India and turn them into opium. The British smuggled opium into China so that they could buy tea. This was one of the reasons the Opium Wars happened, when Britain and China fought with each other. After the Opium Wars, the two countries signed three different treaties with the Qing Empire, who controlled China at the time.