Why was the manitoba province created?

Rupert's land which was a territory in British north america ceded to Canada in the year 1869 which resulted into the incorporation of northwest territories of the north west. Negotiations between the provisional government and the Canadian government resulted in the passage of the Manitoba act which created the province of Manitoba which is Canada's fifth most populated province by the parliament of Canada to decrease the tension between the Canadian government and metis people.

river is shown in this type of map