Opium is a narcotic, addictive substance made from the dried latex from the seed pod of the opium poppy. By the 18th century, smoking opium had become a common addiction in China. Approximately 10 million people, out of a population of 400 million, were addicted. Although initially a fad of the rich upper class in China, opium use spread to government officials, merchants, soldiers, students, servants, and even priests, monks, and nuns. In 1729 the Chinese government made it illegal to sell or use opium. Soon after, the emperor banned the cultivation of the poppy inside China, and in 1800 forbade importation of the drug. The British East India Company pretended to give up their connections to the opium trade, but in reality English vessels called "country ships" began to bring opium from India to China. Americans also smuggled opium, usually from the Turkish port of Smyrna, into China until the war of 1812 interrupted American shipping. During this period, Americans stranded in Canton by the war became middlemen for the English opium traders. After the War of 1812, the American share of the drug trade increased, climbing to 20% of the total drug importation into China. The illegal opium trade was very profitable for American firms, with the exception of several companies who refused to participate. Opium smuggling was a corrupting influence on Chinese customs officials as well.