The Assiniboine are a Siouan-speaking people closely related linguistically to the Sioux and Stoney. Folk tradition suggesting a separation from the Yanktonai Sioux is not supported linguistically or historically. Linguistically, Nakota is on a continuum with the other Sioux dialects, no closer to one than the other, suggesting that the Assiniboine diverged from the Sioux at the same time the other Sioux dialects were differentiating from one another. The name Assiniboine derives from Ojibwa assini?- pwa? n, “stone enemy,” meaning “stone Sioux”—often with the –ak plural suffix, later a final –t, and by the 19th century the final –n or –ne. Nakota is their name for themselves and the language they speak.
Assiniboines were first encountered by Europeans in the woodlands and parklands, already adept canoe users in their role as trade middlemen. In 1737 La Vérendrye distinguished the Woodland Assiniboines, who knew how to take fur-bearing animals, from the Plains Assiniboines, who had to be taught. Communal buffalo hunting utilized dogs until horses were acquired. Assiniboines utilized the buffalo pound to entrap and process much larger quantities than could be taken by single hunters. In the 17th century Assiniboine territory extended westward from Lake Winnipeg and the Forks of the Red and Assiniboine rivers into much of central and southern Saskatchewan. From the earliest descriptions, the Assiniboines allied with Algonquian-speaking Crees, and later, in the early to mid-19th century, with Saulteaux or western Ojibwas. Historical sources suggest a westward expansion of Assiniboine territory during the 18th century through the parklands of the central Saskatchewan River and into eastern Alberta; but these farthest reaches represented interaction spheres, and not a migration of fully articulated social groups reflecting the fur traders’ knowledge of the western prairies. Alexander Henry the Younger listed in 1808 only one of eight Assiniboine bands occupying territory within the boundaries of the United States, along the Souris River in North Dakota. Population movements during the early 19th century shifted Assiniboine territory southward, and by 1840 three-quarters of the nation lived along the Missouri in the area of northwestern North Dakota and northeastern Montana. By the mid-19th century Assiniboine territory extended east from the Moose and Wood mountains to the Cypress Hills, and north to south from the North Saskatchewan River to the Milk and Missouri rivers. Assiniboines first learned of the jurisdiction of the United States with the visit of Lewis and Clark, which marked the beginning of their incorporation.
The population history of the Assiniboines remains incomplete until well into the 19th century. A number of major disease episodes proved to be quite intrusive. The population was estimated at 10,000 before one-half to two-thirds were wiped out in the smallpox epidemic of 1780–81; the 1819–20 epidemic of measles and whooping cough again reduced the population by one-half. After the steamboats brought smallpox to the upper Missouri in the late 1830s the population began to recover, but as much as 60% of the population had been lost. After a slow recovery, two more smallpox epidemics struck the Assiniboine in 1856–57 and in 1869 before the population began another recovery.
By the last decades of the 19th century Assiniboine reservations and reserves were located in Montana and Saskatchewan within the larger region they had occupied during the previous century. In Montana, the Upper Assiniboines were located with the Atsina Gros Ventre on the Fort Belknap Reservation, and the Lower Assiniboines with Yanktonai, Sisseton/Wahpeton Dakota and a small number of Hunkpapa and other Teton stragglers of Sitting Bull’s followers on the Fort Peck Reservation. In Saskatchewan, Assiniboines within Treaty 4 were the reserve bands of Pheasant’s Rump, Ocean Man, Carry the Kettle and Long Lodge, and Piapot’s Cree-speaking Assiniboines; and Assiniboines within Treaty 6 were the bands of Grizzly Bear’s Head and Lean Man, which often were known as the Battleford Stoneys.
Assiniboine population figures in the initial reservation/reserve period were complicated by tribally undifferentiated figures for the shared reservations in Montana, and similarly for some of the reserves in Canada. Contemporary population figures reflect the mixed heritage of many intermarriages: Carry the Kettle 2,009; Ocean Man 346; Pheasant Rump Nakota 316; White Bear 1,898; Mosquito, Grizzley Bear’s Head 1,049; Fort Belknap 2,245; and Fort Peck 4,197. Reservations in Montana and reserves in Saskatchewan remain homes for these respective tribes and First Nations. In every case a large proportion of their populations reside off-reserve, mostly in cities, encouraged to do so both by increased economic opportunities and by various government policy initiatives in the decades following World War II. Since the 1970s, Nakota reserves in Saskatchewan have been leaders in the successful pursuit of land claims known as “specific claims,” and this has resulted in resources for a wide range of economic development initiatives. A florescence of religious practice has occurred in the last three decades, as communities support one another in their search for health and well-being.