This ancient name is now obsolete, having been superseded by the modern Ojibwa term Buanag , of uncertain etymology.
They call themselves Dakota, Nakota, or Lakota, according to dialect, meaning "allies".
When first noticed in history, about 1650, they centered about Mille Lac and Leech Lake, toward the heads of the Mississippi, in central Minnesota, having their eastern frontier within a day's march of Lake Superior.
At the beginning of treaty relations in 1805 they were the acknowledged owners of most of the territory extending from central Wisconsin, across the Mississippi and Missouri, to beyond the Black Hills, and from the Canada boundary to the North Platte, including all of Southern Minnesota, with considerable portions of Wisconsin and Iowa, most of North Dakota and South Dakota, Northern Nebraska, and much of Montana and Wyoming.From the forms Dakota, Lakota, and Sioux are derived numerous place-names within their ancient area, including those of two great states.Linguistically the Sioux are of the great Siouan stock, to which they have given name and of which they themselves now constitute nearly three-fourths.The largest and most important Indian tribe north of Mexico, with the single exception of the Ojibwa ( Chippewa ), who, however, lack the solidarity of the Sioux, being widely scattered on both sides of the international boundary, while the Sioux are virtually all within the United States and up to a comparatively recent period kept up close connection among the various bands.The name Sioux (pronounced Su ) is an abbreviation of the French spelling of the name by which they were anciently known to their eastern Algonquian neighbours and enemies, viz. little, or secondary enemies, as distinguished from the eastern Nadowe, or enemies, the Iroquois.The tribal war went on, but the Sioux kept friendship with the French traders, who by this time had reached the Mississippi.In 1680 one of their war parties, descending the Mississippi against the Illinois, captured the Recollect Father Louis Hennepin with two companions and brought them to their villages at the head of the river, where they held them, more as guests than prisoners, until released on the arrival of the trader, Du Luth, in the fall.Among those killed was the Jesuit father, Jean-Pierre Aulneau.In 1745-6, the Foxes having been finally crushed, De Lusignan again arranged peace with the Sioux, and between them and the Ojibwa, and four Sioux chiefs returned with him to Montreal.About the year 1698, through injudiciously assisting the Sioux against the Foxes, the French became involved in a tedious forty-years' war with the latter tribe which completely paralyzed trade on the upper Mississippi and ultimately ruined the Foxes.Before its end the Sioux themselves turned against the French and gave refuge to the defeated Foxes.