I have found Eric Jay Dolin's book, Fur, Fortune, and Empire: The Epic History of the Fur Trade in America (New York: Norton & Co., 2010) on our Canadian bookstore shelves.
If you want to know the history of the American fur trade -- the early settlers, the ousting of the British from places like Fort Michilimackinac and Detroit in late 1700's; the Americans heading west up the Missouri River; the founding of Astoria; the Mountain men who threatened Peter Skene Ogden, and the buffalo hunts -- this is the book for you.
It is perhaps the American view of books such as David Lavender's Winner Take All: the Trans-Canada Canoe Trail (New York: McGraw-Hill, 1977), which tells of the explorations made by the early fur trade companies through the Great Lakes onto the Saskatchewan River.
Our Beaulieus might have been at Michilimackinac or Detroit; one of them may also have been in some of the areas the Mountain men trapped in.
This is American history, but it affects our history and is the background to many of our fur trade stories.
I am looking forward to reading it.