When Lewis and Clark reached Arikara settlements in 1804, the inhabitants did not show hostility to the expedition. In 1806, during a trip to the United States capital, an Arikara leader died, and many Arikara believed that Americans were involved in his death. Later, as a result of the growing activity of fur trading companies, contact between Arikara and white merchants became more frequent, and skirmishes eventually followed. In the start of 1823, the Arikara "attacked the Missouri Fur Company's Fort Recovery [a trading post for the Sioux] and killed two traders".