The Opium Wars were two mid-19th-century conflicts between China's Qing Dynasty and Western powers, primarily Great Britain. The first war began after Chinese officials seized and destroyed massive stockpiles of opium being smuggled into the country by British merchants. The British responded with superior naval power, forcing China to sign the Treaty of Nanking in 1842. This 'Unequal Treaty' forced China to open five ports to foreign trade and cede the island of Hong Kong to the British. The wars marked the beginning of what Chinese historians call the 'Century of Humiliation,' during which China lost significant sovereignty to foreign powers. It also demonstrated the devastating military gap between industrialized European nations and the traditional Qing Empire, triggering internal Chinese movements for modernization and reform.