* French: This is the primary language of the time and place he lived. He was born and raised in Quebec, Canada, which was a French colony.
* Algonquin: Jolliet explored and mapped the Mississippi River, navigating with the help of Indigenous guides. Algonquin languages, like Ojibwe, were widely spoken in the region, making it essential for Jolliet to communicate with them.
* Possibly some Iroquoian languages: The Iroquoian languages were spoken by nations like the Huron and Seneca, who interacted with the French fur traders and explorers. It's likely Jolliet encountered these languages during his expeditions.
Therefore, we can be confident that Louis Jolliet spoke French and Algonquin, and it's plausible he had some knowledge of other Indigenous languages spoken in the region.