In 1870 ….
Three years after Confederation, the Government of Canada acquired Rupert’s Land from the HBC for CAD$1.5-million (£300,000). It is the largest real estate transaction (by land area) in the country’s history. The purchase of Rupert’s Land transformed Canada geographically. It changed from a modest country in the northeast of the continent into an expansive one that reached across North America. Rupert’s Land was eventually divided among Quebec, Ontario, Manitoba, Saskatchewan, Alberta and the Northwest Territories.
Source : https://thecanadianencyclopedia.ca/en/article/ruperts-land