Exploration of the interior was an intended by-product of the fur trades conducted out of Montréal and Hudson Bay. Traders from Montréal frequented Lake Winnipeg by the 1730s (French Exploration, 17th, 18th Centuries), and established posts on the Saskatchewan River by the 1750s (France Secures the Interior, 1740-1755, Concise Plate 44; Vol I, pl 40). Although the Hudson's Bay Company did not open an interior trading post until 1774, as early as 1691 one of its young traders, Henry Kelsey, crossed the boreal forest and the parkland belt to reach the edge of the grasslands, and then wintered with Indian bands on their trapping grounds. After 1754 HBC traders visited the parkland and grasslands annually; one of them, Anthony Henday, may have been the first European to see the Rocky Mountains from the Canadian plains.
In 1772 another HBC employee, Samuel Hearne, finally succeeded in crossing the barren ground to reach the Arctic Ocean at the mouth of the Coppermine River. He found native reports of rich deposits of copper to be greatly exaggerated, and demonstrated that there was not a water passage to the Pacific from Hudson Bay. Navigators had long probed the inlets of the northwestern bay, looking for such a passage (Exploring the Atlantic Coast, 16th, 17th Centuries).
The coast of Labrador was explored in the 16th century (Exploring the Atlantic Coast, 16th, 17th Centuries), and the east coast of Hudson Bay and James Bay (the Eastmain) in the 17th century, but the interior of the Quebéc-Labrador peninsula long remained unknown to Europeans. When the HBC was founded, French traders opened a route between the St Lawrence and James Bay (French Exploration, 17th, 18th Centuries): later they pushed some distance up the major rivers flowing into the Gulf of St Lawrence from the north. Thus was defined the perimeter of a vast, unknown land. In 1775 there were two Moravian missions on the Labrador coast and two trading posts on the Eastmain.
Over the next 50 years employees of the HBC began to explore inland from the Eastmain. By 1821 they were familiar with the Great Whale, Little Whale, and Eastmain Rivers, and had crossed the height of land to the Caniapiscau River, following it almost to Ungava Bay. The complex drainage system between the Caniapiscau and the mountains along the Labrador coast was not entered until later.