When considering these French Jesuit missionaries, I usually experience a combination of being awestruck by their faith and fortitude on the one hand, and an extreme sense of gratitude for not being a Jesuit in 17th c. New France, on the other. I’m also reminded of the book (and film), Black Robe, which, despite its at times overt anti-Catholic message (i.e. Catholic doctrine is silly and superstitious), gives a sense for what the missionary life was then, the physical hardships it entailed, and, interestingly, the theological question of the “religious other” that would increasingly loom larger in the following centuries, culminating in Nostra Aetate in the 20th c. What follows is a quite graphic description of two of the martyrs deaths (Brébeuf and Lallement)
From New Advent:
On entering the village, they were met with a shower of stones, cruelly beaten with clubs, and then tied to posts to be burned to death. Brébeuf is said to have kissed the stake to which he was bound. The fire was lighted under them, and their bodies slashed with knives. Brébeuf had scalding water poured on his head in mockery of baptism, a collar of red-hot tomahawk-heads placed around his neck, a red-hot iron thrust down his throat, and when he expired his heart was cut out and eaten. Through all the torture he never uttered a groan. The Iroquois withdrew when they had finished their work. The remains of the victims were gathered up subsequently, and the head of Brébeuf is still kept as a relic at the Hôtel-Dieu, Quebec.
You can compare this to the version on Wikipedia here.
North American Martyrs, orate pro nobis!