Great video! If you are interested in the fur trade, you will probably like FUR, FORTUNE, AND EMPIRE: THE EPIC HISTORY OF THE FUR TRADE IN AMERICA (W. W. NORTON, JULY 2010). To see a book trailer for this book, search fur trade history on youtube, or search the title. The book is available in bookstores, online and in stores. I spoke on the fur trade at Fort Laramie earlier this summer.