There are many kinds of poppies, but one has become most infamous: papaver sominferum, also known as the opium poppy. The Chinese, who developed the unripened seed as a pain reliever in the 15th century, passed the first law against the smoking of opium in 1729. Nonetheless, the poppy fields in British India provided a profitable export to China, prompting the Opium Wars of 1839 to 1842. The wars ended with England in possession of Hong Kong and special trade privileges. By the 1990s, heroin, a drug produced from the opium poppy, was a $10 billion per year business in the U.S. alone.