The Opium Wars had significant consequences for China, with the most notable being the enforcement of unequal treaties that favored Western powers. Initiated in the mid-19th century due to China's attempts to suppress the opium trade, the First Opium War (1839-1842) led to China's defeat by British forces. The Treaty of Nanjing (1842) granted Hong Kong to Britain and opened numerous ports to foreign trade. The Second Opium War (1856-1860) further entrenched foreign dominance, resulting in more concessions. Ultimately, these conflicts weakened China's sovereignty, contributing to domestic unrest, and setting the stage for further foreign intervention and the eventual decline of the Qing dynasty.