Charles Garnier was the son of the secretary to the Council of Henry III of France, entered the Society of Jesus in 1624 at eighteen, was ordained in 1635, and sailed for New France in 1636. He served at Sainte-Marie among the Hurons from 1637 and from 1646 at the mission of Saint-Jean among the Petun (Tobacco Nation), the Iroquoian-speaking confederation west and south of the Huron — a small mission of two Jesuits and a few donnés.
On December 7, 1649 — nine months after the destruction of Brébeuf and Lalemant at Saint-Ignace and the wider collapse of the Huron Confederacy — an Iroquois war party crashed into the Petun village of Étarita where Garnier was minister. He was shot twice with arquebus fire while administering baptism to a kneeling Petun convert in the burning village; rising once more to give absolution to another fallen woman, he was struck by a tomahawk and died. Canonized 1930.