First Opium War (1839-1842): This was the first major conflict of the Opium Wars. It began when China attempted to suppress the opium trade. British forces responded with military action resulting in their victory and signing of Treaty of Nanking.
Second Opium War (1856-1860): The second major conflict in which Britain and France fought against China due to disputes over treaty rights, diplomatic respect and legalised opium trade. The war ended with another defeat for China and signing of Treaty of Tientsin.
Treaty of Nanking: Signed after First Opium War in 1842 between UK and Qing dynasty China that ended hostilities and opened up five ports for foreign trade along with cession of Hong Kong Island.