The Opium Wars in China were primarily caused by British trade in opium, which created widespread addiction and social disruption in China. In the early 19th century, Britain exported opium from India to China, leading to a significant outflow of silver and a trade imbalance. The Chinese government's attempts to curtail opium use and trade, culminating in the destruction of opium stocks, prompted Britain to retaliate militarily. The First Opium War (1839-1842) and the Second Opium War (1856-1860) resulted in unfavorable treaties for China, expanding Western influence and cementing the opium trade.