Forty Years a Fur Trader on the Upper Missouri immerses the reader in the life of a merchant in the Missouri River from the 1830s to the early 1870s. An autobiographical chronicle which sheds a light into a period and profession of history often ignored in the modern day, Forty Years a Fur Trader is an illuminating and lively chronicle of Charles Larpenteur's career as a fur seller. A man of tough resolve and hardy constitution, Larpenteur condenses his many years traversing the Missouri wilderness and trading posts into a series of episodic highlights, chronologically arranged. The Missouri River and Rocky Mountains were, at the time, dangerous but potentially lucrative proposition for a trader to undertake. Rough terrain, numerous wild animals, and the presence of Native American tribes made life as a fur trader unpredictable and fraught with danger. Yet a good set of high quality pelts would fetch high sums, demand being high especially for animals whose fur had scarcely before seen market.