The peace pipe was often called a "calumet," a Norman-French work coined
by the first French traders.  The calumet was used throughout the Great
Plains and eastern woodlands.  It had many purposes.  By smoking tobacco
in it, a white traveler was guarantee d safe conduct; by carrying one
(each had a unique decorations), a calumet became a means of
identification.  Peace pipes were employed to ratify a variety of
agreements, political as well as commercial.  They were also used in
conjunction with the rain dance, and in the blessing of crops.  Shown
here is General Winfield Scott Hancock, second from the right, smoking a
peace pipe with an Arapaho chief in 1867.