The abolition of the factory system left a vacuum within the U.S. government regarding Native American relations. The current Bureau of Indian Affairs was formed on March 11, 1824, by Secretary of War John C. Calhoun, who created the agency without authorization from the United States Congress. McKenney was appointed the first head of the office, which went by several names at first. McKenney preferred to call it the "Indian Office", whereas the current name was preferred by Calhoun. Like its predecessors, the bureau was originally a division of the Department of War. In 1849 it was transferred to the Department of the Interior. The bureau was renamed to Bureau of Indian Affairs in 1947 (from the original Office of Indian Affairs).
for more info:
http://en.wikipedia.org/wiki/Bureau_of_Indian_Affairs
for more info:
http://en.wikipedia.org/wiki/Bureau_of_Indian_Affairs