David Thompson's Narrative was a published and more in-depth version of his own personal journal. David Thompson was a cartographer and mapped regions of Canada and the United States being described as the "Greatest land geographer who ever lived." His narrative documented his travels and contact with the natives, as well as animals and landmarks he had seen on his way. What is important, though, is that he made the earliest known written account of Sasquatch.

The account was believed to have occurred in Jasper, Alberta in 1811 and goes like this:

"January 7th. Continuing our journey in the afternoon we came on the track of a large animal, the snow about six inches deep on the ice; I measured it; four large toes each of four inches in length to each a short claw ; the ball of the foot sunk three inches lower than the toes, the hinder part of the foot did not mark well, the length fourteen inches, by eight inches in breadth, walking from north to south, and having passed about six hours. We were in no humour to follow him: the Men and Indians would have it to be a young mammoth and I held it to be the track of a large old grizled Bear; yet the shortness of the nails, the ball of the foot, and it's great size was not that of a Bear, otherwise that of a very large old Bear, his claws worn away; this the Indians would not allow."

Later in the book he recalls another story:

"I now recur to what I have already noticed in the early part of last winter, when proceeding up the Athabasca River to cross the Mountains, in company with . . . Men and four hunters, on one of the channels of the River we came to the track of a large animal, which measured fourteen inches in length by eight inches in breadth by a tape Hne. As the snow was about six inches in depth the track was well defined, and we could see it for a full one hundred yards from us, this animal was proceeding from north to south. We did not attempt to follow it, we had no time for it, and the Hunters, eager as they are to follow and shoot every animal made no attempt to follow this beast, for what could the balls of our fowling guns do against such an animal. Report from old times had made the head branches of this River, and the Mountains in the vicinity the abode of one, or more, very large animals, to which I never appeared to give credence ; for these reports appeared to arise from that fondness for the marvellous so common to mankind ; but the sight of the track of that large beast staggered me, and I often thought of it, yet never could bring myself to believe such an animal existed, but thought it might be the track of some monster Bear."