Question: This group of natives in North America were indigenous to the Interior Plains, historically nomadic, and relied on bison hunting.
Context: Cow Creek is a tributary of the Missouri River, approximately 35 mi long, in north central Montana in the United States.  Cow Creek rises in the southern foothills of the Bear Paw Mountains in western Blaine County and flows east and then south, joining the Missouri approximately 25 mi northeast of Winifred, Montana—or 22 mi upstream from the Fred Robinson Bridge.  Cow Creek flows down to the Missouri in a canyon that passes through the Missouri Breaks, which are severely eroded badlands that extend out on either side from the Missouri River.  The floor of Cow Creek canyon provided a pathway of travel from the Montana plains north of the river, down to the Missouri – at the mouth of Cow Creek, Cow Island made fording the Missouri easier – a steep but short trail on the south bank of the Missouri opposite Cow Creek completed this route which led from the northern Montana plains to the central and southern Montana plains.  This pathway was used by migrating buffalo/bison and nomadic American Natives for centuries.  During the steamboat era on the Missouri River, when low water prevented riverboats getting up to Fort Benton, the mouth of Cow Creek became a river landing and freighting depot, and it was the start of the Cow Island Trail by which freight was moved on to Fort Benton by going north up Cow Creek and then west.  In 1877 the Nez Perce Indian Tribe, fleeing to Canada, had several skirmishes along Cow Creek including the "Battle of Cow Island", and several days later at a camp on Cow Creek the Nez Perce, thinking themselves now beyond the reach of the U.S. Army, made the fateful decision to slow down, rather than push on for the Canada–US border.  Today, modern highways have by passed Cow Creek, and the buffalo and the nomadic Indian are gone.  Cow Creek is dormant, in one of the most remote spots of the isolated regions of the vast area known as the Montana Missouri Breaks. A buffalo coat is a heavy winter garment made from the bison, which also commonly known as the "buffalo" (though not closely related to African or Asian buffaloes).  In North America they descended from the simpler, sleeveless buffalo robes worn by the Indigenous peoples of North America prior to their partial replacement by capotes made of point blankets during the North American fur trade.  Similar garments were also used across Eurasia prior to the gradual displacement and near-extinction of the European bison or wisent.  Commercially produced coats with sleeves and buttons became popular with non-indigenous people during the early settlement period of the American West and the Canadian prairies.  Their use mostly ended because of a rising conservationist movement intended to preserve the bison, which had been hunted to near-extinction in North America as well. The American bison ("Bison bison"), also commonly known as the American buffalo or simply buffalo, is a North American species of bison that once roamed the grasslands of North America in massive herds.  They became nearly extinct by a combination of commercial hunting and slaughter in the 19th century and introduction of bovine diseases from domestic cattle, and have made a recent resurgence largely restricted to a few national parks and reserves.  Their historical range roughly comprised a triangle between the Great Bear Lake in Canada's far northwest, south to the Mexican states of Durango and Nuevo León, and east to the Atlantic Seaboard of the United States (nearly to the Atlantic tidewater in some areas) from New York to Georgia and per some sources down to Florida.  Bison were seen in North Carolina near Buffalo Ford on the Catawba River as late as 1750. Throughout the 18th and 19th centuries, the plains bison and wood bison populations were hunted by nomadic indigenous hunters and white hunters alike.  By the 1850s, the bison was nearly extinct, spurring a movement to save the few herds that remained.  Federal government wildlife policy evolved from preservation of wilderness to utilitarian, scientific conservation and management of bison populations.  The goals of these policies often contradicted themselves, aiming to simultaneously preserve wildlife, promote recreation, commercialize the bison, and assert state control over Aboriginal peoples.  Bison conservation efforts were shaped by the federal government's colonialist and modernist approach to Canada's north, the management of national parks and reserves, and the influence of scientific knowledge. Bison hunting (hunting of the American bison, also commonly known as the American buffalo) was an activity fundamental to the economy and society of the Plains Indians peoples who inhabited the vast grasslands on the Interior Plains of North America, prior to the animal's near-extinction in the late nineteenth century.  The species' dramatic decline was the result of habitat loss due to the expansion of ranching and farming in western North America, industrial-scale hunting practised by non-indigenous hunters, increased indigenous hunting pressure due to non-indigenous demand for bison hides and meat, and even cases of deliberate policy by settler governments to destroy the food source of the native Indian peoples during times of conflict.  Bison were first hunted for their meat, but now they are hunted for sport. Plains Indians, Interior Plains Indians or Indigenous people of the Great Plains and Canadian Prairies are the Native American tribes and First Nation band governments who have traditionally lived on the greater Interior Plains (i.e. the Great Plains and the Canadian Prairies) in North America.  Their historic nomadic culture and development of equestrian culture and resistance to domination by the government and military forces of Canada and the United States have made the Plains Indian culture groups an archetype in literature and art for American Indians everywhere. The Wind Cave bison herd is a herd of 250–400 American bison in Wind Cave National Park, South Dakota, USA.  It is believed to be one of only four free roaming and genetically pure herds on public lands in North America.  The other three herds are the Yellowstone Park bison herd, the Henry Mountains bison herd in Central Utah, and at Elk Island National Park in Alberta, Canada.  The Wind Cave herd are of the Plains bison subspecies ("Bison bison bison"). The Interior Plains is a vast physiographic region that spreads across the Laurentian craton of central North America.  The region extends from the Gulf Coast region to the Arctic Ocean along the east flank of the Rocky Mountains.  In Canada the region separates the Rocky Mountains from the Canadian Shield.  In the United States the plains include the Great Plains of the west and the Tallgrass prairie region to the south of the Great Lakes extending east to the Appalachian Plateau region. The Osage Plains are a physiographic section of the larger Central Lowland province, which in turn is part of the larger Interior Plains physiographic division.  The area is sometimes called the Lower Plains, North Central Plains, and the Rolling Plains.  The Osage Plains, covering west-central Missouri, the southeastern third of Kansas, most of central Oklahoma, and extending into north-central Texas, is the southernmost of three tallgrass prairie physiographic areas.  It grades into savanna and woodland to the east and south, and into shorter mixed-grass prairie to the west.  The Osage Plains consist of three subregions.  The Osage Plains proper occupy the northeast segment.  Although sharply demarcated from the Ozark uplift, the Plains are nonetheless a transitional area across which the boundary between prairie and woodland has shifted over time.  In the central portion of the physiographic area lies the second subregion, the Flint Hills, commonly called "The Osage" in Oklahoma.  This large remnant core of native tallgrass prairie is a rocky rolling terrain that run from north to south across Kansas and extends into Oklahoma.  To the west and south of these hills are the Blackland Prairies and Cross Timbers.  This vegetatively complex region of intermixed prairie and scrubby juniper-mesquite woodland extends into north-central Texas.  Bluestem prairies and oak-dominated savannas and woodlands characterize the natural vegetation in the Cross Timbers.  Much of the area has been converted to agriculture, although expanses of oak forest and woodland are still scattered throughout the eastern portion of the subregion. Bison occidentalis is an extinct species of bison that lived in North America from about 11,000 to 5,000 years ago, spanning the end of the Pleistocene to the mid-Holocene.  Likely evolving from "Bison antiquus", "B. occidentalis" was smaller overall from its ancestor and other species such as the steppe bison.  "B. occidentalis" had a highly variable morphology, and their horns, which pointed rearward, were much thinner and pointed than Pleistocene species of bison.  Around 5,000 years ago, "B. occidentalis" was replaced by today's smaller "Bison bison".
Answer: Plains Indians