Girard was a parfait living in France.
He was unwilling to refuse refuge to anyone coming to the Roc of the Cathares. Unable to deal with the situation for much longer, Girard negotiated a surrender to the Catholic army.
However, before that happened, he wanted to make sure a valuable relic did not fall into their hands. Girard believed it to be the skull of Jesus Christ. Jeanne was searching for it so she could sell the relic and use the money to free her sons. When Girard would not reveal the location, Jeanne killed him. Ironically, the Seventh Doctor determined that the relic was a fake, in part because it was that of a woman. (PROSE: Sanctuary)