Bio: Mathis was a member of the French Deuxième Bureau, roughly the French equivalent of the CIA or MI6. He was one of James Bond's earliest "international partners". Flashbacks in various novels suggest that Mathis met Bond before even Felix Leiter, probably before Bond got Double-O status.
Notes: Mathis debuted in all versions of Casino Royale, alongside the higher-profile Bond buddy, Felix Leiter. However, if one's only exposure to Bond is the films, you may believe he's a creation of 21st-century filmmakers. Because of contested film rights, Casino Royale didn't receive treatment in the "official" MGM/EON film franchise until 2006.