The first trading post on Cumberland lake was built by Joseph Frobisher 1772 free-trader at the time. Cumberland lake was then known as Pine Island lake, and Sturgeon lake. This fort was built for the purpose of intercepting the Indians going to Fort Nelson. It was built close to portage to Gull lake, not far from the site formerly occupied by the French Fort Pascoyac. It was a temporary structure and was soon replaced.

The second fort on Cumberland lake was built by Samuel Hearne for the Hudson's Bay Co. in 1774. It was called Cumberland House, situated at east end of the lake, near portage to Gull lake, where it leaves Cumberland lake. The name was given by Hearne in honour of Prince Rupert, Duke of Cumberland, first Governor of Hudson's Bay Co. This fort has always been maintained since 1774. It is the oldest post of Hudson's Bay Co. in the interior, for although Henley House, Split Lake House, and Nelson House, were built between 1740 and 1750, these posts are near the Bay and only nominally inland. It is a strategic point as two routes open thence to the interior, west and south by Saskatchewan river, northwest and north to the upper Churchill country. The Hudson's Bay Co. post was located about 500 yards from Frobisher's House of 1772, on the south shore, "on the Saskatchewan river at a spot where it is touched by Cumberland lake". It was built on an island at the southeast end of Pine Island lake, about 4 miles north of the Saskatchewan river, into which are three outlets from the lake, namely, Big Stone river immediately in the rear and west of the fort, Tearing river 4 miles to east, and Fishing Weir creek farther east. Pine island is made by the lake on the north, Saskatchewan river on south, Big Stone river on the west, and Tearing river on the east.

In 1780 the North West Co. constructed their new fort (also called Cumberland House or Station) about 100 yards from Hudson's Bay Co. and about 1&fract12; miles west of the first house built by Frobisher 1772. Henry Jr. was there in 1808 and describes it as being at the north end of this little river called Little English river, i.e. the Tearing river. This fort was sometimes called Fort Sturgeon Lake, but in general both Companies used the same name, Cumberland House. This was the first permanent post of the North West Co. on Cumberland lake and was maintained by them until the coalition 1821. In 1775, when Alexander Henry Sr. passed, there was only the Hudson's Bay Co. post, Frobisher's post of 1772 having disappeared.

There was also an X. Y. Co. post near by.