Born into an aristocratic family in Strasbourg, France, Charles was orphaned at the age of six, raised by his devout grandfather, rejected the Catholic faith as a teenager and joined the French army. Inheriting a great deal of money from his grandfather, Charles went to Algeria with his regiment, but not without his mistress, Mimi.

When he refused to give her up, he was dismissed from the army. Later he reenlisted in Algeria after he had left Mimi. He resigned from the army when he was refused permission to make a scientific exploration of nearby Morocco. With the help of a Jewish rabbi, Charles disguised himself as a Jew and in 1883 began a one-year exploration that he recorded in a book that was well received.

Inspired by the Jews and Muslims whom he met, when he returned to France he resumed the practice of his Catholic faith in 1886. He joined a Trappist monastery in Ardeche, France, and later transferred to one in Akbes, Syria. He left them and in 1897 began to work as gardener and sacristan for the Poor Clares nuns in Nazareth and later in Jerusalem. He returned to France and was ordained a priest in 1901.

Later that year he returned to Beni-Abbes, Morocco, intending to found a monastic religious community in North Africa, offering hospitality to Christians, Muslims, Jews or people with no religion. He lived a peaceful, hidden life but attracted no companions.

A former army comrade invited him to live among the Tuareg people in Algeria. Charles learned their language enough to write a Tuareg-French and French-Taureg dictionary and to translate the Gospels into Tuareg. In 1905 he came to Tamanrasset, where he lived the rest of his life. His two-volume collection of Tuareg poetry was published after his death.

In early 1909 he visited France and established an association of laypeople who pledged to live by the Gospels. His return to Tamanrasset was welcomed by the Tuareg. In 1915 he wrote to Louis Massignon: “The love of God, the love for one’s neighbor…All religion is found there…How to get to that point? Not in a day since it is perfection itself: it is the goal we must always aim for, which we must unceasingly try to reach and that we will only attain in heaven.”  

The outbreak of World War I led to attacks on the French in Algeria. Seized in a raid by another tribe, Charles and two French soldiers coming to visit him were shot to death on December 1, 1916.

Five religious congregations, associations and spiritual institutes (Little Brothers of Jesus, Little Sisters of the Sacred Heart, Little Sisters of Jesus, Little Brothers of the Gospel and Little Sisters of the Gospel) draw inspiration from the peaceful, largely hidden yet hospitable life that characterized Charles. He was beatified on November 13, 2005.