Martin Ladvenu, Dominican, from the Jacobin monastery at Rouen, who sought to enlighten Jeanne, was her confessor, and her spiritual adviser in prison.

Very little is known about Martin Ladvenu.
He was in Paris at the time of the trial of Gilles Deschamps, one of Jeanne's judges.
The following year at Neufchatel he lectured a sorceress, Jeanne Vaneril, suspect in matters of faith.

He was described, in 1452, at the time of the preliminary process of the Rehabilitation, as a friar of the monastery of the Jacobins at Rouen, "especial confessor and adviser of the maid Jeanne in her last days."