The history regarding this pass begins with James Sinclair leading a party of Red River immigrants through the pass in 1841. In his book "The Place of Bows," E.J. Hart suggests that although the party was made up largely of Metis, the presence of a few men from the Maritimes, "seem to account for the name 'Whiteman's' being attached to the pass."
Then, in 1846, Pierre-Jean De Smet and by British army Lieutenants Henry James Warre and Mervin Vavasour are said to have met near the summit. Few Europeans were travelling in the southern Rockies at this time and it was a remarkable coincidence that the two parties met (Esther Fraser, "The Canadian Rockies" wrote that Warre and Vavasour "probably" used this pass).
Father de Smet built a cross that he referred to as the, "Cross of Peace" near the summit of the pass, hence the origin of the name for the Cross River that flows west from the summit. He wrote, "The Christian's standard, the cross has been reared at the sources of these two rivers. May it be a sign of salvation and peace to all the scattered and itinerant tribes east and west of these gigantic an luid mountains."
Lts. 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 what is now Canada. The trip had been encouraged by George Simpson of the Hudson Bay Company. Warre and Vavasour reported that the mountain passes were unsuitable for troop transport.
Of this pass and others, they wrote: "Without attempting to describe the numerous Defiles through which we passed, or the difficulty of forcing a passage through the burnt Forests, and over the high land, we may venture to assert, that Sir George Simpson's idea of transporting troops. . . with their stores, etc. through such an extent of uncultivated Country and over such impracticable Mounatins would appear to Us quite unfeasible."
[Additional information: "The Canadian Rockies" by Esther Fraser]