IC: Colonial Gothic in the northern wilderness
If I could recommend only one source it would be Black Robe, the 1991 film, or the book it's based on. It captures the characters and themes very well. I haven’t settled on the exact decade yet, but we’ll probably be playing around 75 years after the events of that film.
I haven’t seen Barkskins, the new NG TV series based on 17th C Quebec. It looks good, but perhaps more Eurocentric.
Print sources are many, and I’m open to suggestions. I’m currently reading Hunt’s “The Wars of the Iroquois”. For PC backgrounds, Wikipedia does a pretty good job of providing little regional details for characters’ cultural and historical origins, French PCs in particular; indigenous characters less so.
The Colonial Gothic source material really isn’t detailed enough to be of use: it covers a vast historical and geographical area. There’s no reason not to buy the books, but I wouldn’t rush out to get them, since the ruleset is easy enough to learn and we won’t be sticking closely to the fantasy lore presented there. It’s the sort of game you can have fun with learning on the fly.