The Saskatchewan River (Cree: kisiskāciwani-sīpiy, "swift flowing river") is a major river in Canada, approximately 550 km (340 mi) long, flowing roughly eastward across Saskatchewan and Manitoba to drain into Lake Winnipeg. Through its tributaries the North Saskatchewan and South Saskatchewan, its watershed encompasses much of the prairie regions of central Canada, stretching westward to the Rocky Mountains in Alberta and into northern Montana in the United States. It reaches approximately to its furthest headwaters on the Bow River, a tributary of the South Saskatchewan in Alberta .
It is formed in central Saskatchewan, approximately 40 km (25 mi) east of Prince Albert, by the confluence of its two major branches, the North Saskatchewan and the South Saskatchewan, at the Saskatchewan River Forks. Both source rivers originate from glaciers in the Alberta Rockies.
The combined stream flows east-northeast, into Codette Lake formed by the Francis Finlay dam at Nipawin then into Tobin Lake, formed by the E. B. Campbell Dam. It then flows northeast, off the edge of the prairies of the Great Plains onto the Canadian Shield, passing through a region of marshes, where it is joined from the northwest by the Torch River and the Mossy River. At the northern edge of the marshes it flows east, twisting between a series of small lakes into west-central Manitoba to The Pas, where it is joined from the southwest by the Carrot River. Southeast of The Pas, it forms several streams in a delta on the northwest side of Cedar Lake, then exiting the lake on its southeast end and flowing approximately 5 km (3 mi) to Lake Winnipeg, entering on the northwest shore north of Long Point.
The river, like the province of Saskatchewan, takes its name from the Cree word kisiskāciwani-sīpiy, meaning "swift flowing river". The river and its tributaries provided an important route of transportation for First Nations and early European trappers.
Henry Kelsey penetrated the area in the 1690s for the Hudson's Bay Company, and Louis de la Corne, Chevalier de la Corne established the furthest western post of the French Empire in America (See New France) just east of the Saskatchewan River Forks at Fort de la Corne. In addition to this the Hudson's Bay Company and North West Company both ran numerous fur posts up the river and its two branches throughout the late eighteenth to late nineteenth centuries. York boats and canoes formed the primary means of travel during the fur trade period.
The earliest settlements in Saskatchewan and Alberta generally were established around the rivers. Examples include Fort Edmonton (Edmonton, Alberta), Fort Battleford (Battleford, Saskatchewan), Prince Albert, Saskatchewan, and Cumberland House, Saskatchewan.