Our Ancestors and their Connection with Fur Trader LeBlanc

 

Sometimes the contracts our ancestors signed tell us more about their lives than any census or church record ever could. Take my 5th great-uncle, Michel Vielle dit Cosse (1771–1810), born in St-Joseph, Chambly, Quebec, and buried at La Prairie de la Madeleine. Like so many French-Canadian men from the La Prairie area, Michel became a voyageur—one of the legendary canoe men who powered the North American fur trade.

In March 1793, at age 21, Michel signed a three-year contract with McTavish, Frobisher & Company (the core of the North West Company). He hired on as an avant—the bowsman who stood in the front of the canoe, steering through rapids and guiding the brigade on the long haul to the far northwest. It was dangerous, backbreaking work, but it paid 900 livres plus an advance, and it carried him deep into the pays d’en haut.

Eight years later, in March 1801, Michel signed another engagement—this time with Pierre LeBlanc, a French-Canadian fur trader operating out of the Detroit region. The destination was left blank on the contract, but it was almost certainly the Detroit River country. That single line of ink links my uncle directly to one of the most colorful figures in early Michigan history.

Pierre LeBlanc had arrived in the Detroit area around 1790, initially trading for the Hudson’s Bay Company before striking out on his own. In a frontier where French women were scarce, he married a woman of the Fox (Meskwaki) Nation. Together they cleared a homestead farm along what is now West Jefferson Avenue in Ecorse, about eight miles south of Detroit. Their log cabin doubled as the first Catholic chapel in the area; Mass was celebrated within its walls for years. LeBlanc and his wife raised a family that blended French and Indigenous worlds—trading furs, farming, and maintaining strong ties with Native neighbors. Their son Pierre Jr. later became a constable and highway commissioner, helping lay out some of Michigan’s earliest roads. A faded 1824 tax bill for $2.03 (sent by the Wayne County sheriff) and a receipt from a survivor of the 1813 Frenchtown massacre were among the family keepsakes passed down.

The fur trade itself was a meeting ground of cultures. For two centuries, French and British traders competed for territory and Native alliances around the Great Lakes. French traders often relied on Huron-Wyandot and Ottawa middlemen, while the British used generous gifts and better prices to win influence. Individual men like LeBlanc—entrepreneurial, adaptable, and willing to marry across cultural lines—helped create the “middle ground” where European goods, technologies, and ideas mingled with longstanding Indigenous ways of life.

It turns out the LeBlanc name appears in another branch of our family’s fur-trade story. My 6th great-uncle, Charles Lagasse (also spelled Lagacé or La Gassi), was himself a seasoned NWC voyageur. Engaged in 1792 as a gouvernail (steersman), he later worked directly with the legendary map-maker and explorer David Thompson. In the fall of 1800, Thompson sent Charles and a voyageur named LeBlanc (possibly a relative or colleague of the Detroit trader) westward with a group of Kootenay Indians. Their mission: winter among the Kootenay people on the far side of the Rockies and open trade.

They paddled and portaged up the North Saskatchewan River, crossed the continental divide at what we now call Howse Pass, and reached the headwaters of the Columbia River—the first Europeans known to have done so. The two men spent the winter trading and living with the Kootenay before returning east in spring 1801. Their journey, described in Thompson’s journals and later histories such as Parkways of the Canadian Rockies, helped blaze the trail for the NWC’s expansion into the Pacific Northwest.

From the birchbark canoes of the Great Lakes to the mountain passes of the Rockies, our La Prairie ancestors were right in the middle of the adventure. Their contracts and travels remind us that the fur trade wasn’t just about beaver pelts—it was about courage, cultural exchange, and the restless spirit that pushed French-Canadian voyageurs thousands of miles from home.

Sources (for further reading):

• Notary records (e.g., Louis Chaboillez) for the 1793 and 1801 contracts.
• Local histories of Ecorse and the Detroit River fur trade (including accounts of Pierre LeBlanc’s farm and log-cabin chapel).
• David Thompson’s journals and secondary works on the NWC, including references in Parkways of the Canadian Rockies.

At the top of this page is a classic depiction of a North West Company voyageur canoe brigade on the water—exactly the kind of scene Michel Vielle dit Cosse would have known:

And this 1820s-era map (based on David Thompson’s surveys) shows the vast western territories your uncles helped open, including the route through the Rockies near Howse Pass:

Thank you to Grok xAI for the enhanced information about my ancestors. -- Drifting Cowboy