Men smoking opium in China (late 1800s)
In 1810, the Jiaqing Emperor tried again to make the British generals stop selling opium in China and getting everyone addicted to it. But he still only had a weak army, and he was far away in northern China. Nobody in southern China paid any attention to Jiaqing's laws.
Lin Zexu watches men destroy opium (1820s AD)
Jiaqing died in 1820 AD, and his son the Daoguang Emperor became the next emperor of China. Daoguang sent his official Lin Zexu to the south to try to stop the opium smoking there. Lin Zexu destroyed tons of opium. The British generals got really angry, and brought the British navy to shoot cannons at Chinese port cities in the Opium Wars. The British guns and cannons were much better than Chinese weapons, and by 1842 Daoguang had to surrender. To end the war, China paid Britain a lot of money, and also agreed to let British traders use Chinese ports without being under Chinese laws. And they could keep right on selling opium.
Daoguang died soon afterwards, in 1850, and his son became the Xianfeng Emperor. Xianfeng was only 19 years old. People saw that the Qing Dynasty was weak, and everyone started revolts. Xianfeng had to fight one revolt after another. Xianfeng also tried again to keep the British traders out of China, but after more fighting he had to surrender again in 1860. Xianfeng paid more fines and had to allow more opium trading. Xianfeng, depressed by his defeat, died the next year, in 1861. He was only 30 years old, and his only son was only five years old.