There has been much confusion concerning the definition and designation of the Hidatsa Indians. They were formerly known as Minitari or Gros Ventres of the Missouri, in distinction from the Gros Ventres of the plains, who belong to another stock. The origin of the term Gros Ventres is somewhat obscure, and various observers have pointed out its inapplicability, especially to the well-formed Hidatsa tribesmen. According to Dorsey, the French pioneers probably translated a native term referring to a traditional buffalo paunch, which occupies a prominent place in the Hidatsa mythology and which, in early times, led to a dispute and the separation of the Crow from the main group some time in the eighteenth century.
The earlier legends of the Hidatsa are vague, but there is a definite tradition of a migration northward, about 1765, from the neighborhood of Heart river, where they were associated with the Mandan, to Knife river. At least as early as 1796, according to Matthews, there were three villages belonging to this tribe on Knife river-one at the mouth, another half a mile above, and the third and largest 3 miles from the mouth. Here the people were found by Lewis and Clark in 1804, and here they remained until 1837, when the scourge of smallpox fell and many of the people perished, the survivors uniting in a single village. About 1845 the Hidatsa and a part of the Mandan again migrated up the Missouri, and established a village 30 miles by land and 60 miles by water above their old home, within what is now Fort Berthold Reservation. Their population has apparently varied greatly, partly by reason of the ill definition of the tribe by different enumerators, partly by reason of the inroads of smallpox. In 1890 they numbered 522.
The Crow people are known by the Hidatsa as Kihatsa (They-refused-the-paunch), according to Matthews; and Dorsey points out that their own name, Absaruke, does not mean “crow,” but refers to a variety of hawk. Lewis and Clark found the tribe in four bands. In 1817 Brown located them on Yellowstone river. In 1829 they were described by Porter as ranging along Yellowstone river on the eastern side of the Rocky mountains, and numbered at 4,000; while in 1834, according to Drake, they occupied the southern branch of the Yellowstone, about the forty-sixth parallel and one hundred and fifth meridian, with a population of 4,500. In 1842 their number was estimated at 4,000, and they were described as inhabiting the headwaters of the Yellowstone. They have since been duly gathered on the Crow Reservation in Montana, and are slowly adopting civilization. In 1890 they numbered 2,287.