They left Fort Garry (now the city of Winnipeg) in 1841 with 23 families, including a 75-year-old woman, with an aim to settle in the Oregon Country to reinforce British claims to the area.
In 1845, Father Pierre-Jean De Smet, a Jesuit priest, came east from Windermere Lake via the Kootenay River and one of its tributaries to the summit of White Man's Pass "where all was wild sublimity".
Father De Smet and British Army Lieutenants Henry James Warre and Mervin Vavasour are said to have met near the summit.
From White Man's Pass, de Smet travelled down the Spray River, which was "jewelled with enamelled beads", and on out to the foothills (Fraser 1969).
Warre and Vavasour were travelling eastward, returning from a secret mission to determine if troops could be dispatched through the mountains to defend British interests in the southwestern part of the Columbia District.
The Cross River originates in Kootenay National Park on the west slopes of the Continental Divide near White Man Pass, in British Columbia.