Peter Thomas was a 14th-century French Carmelite friar, diplomat, and prelate. Born in Périgord to a poor family, he joined the Carmelite Order and rose to prominence through his roles as a preacher and teacher. He served as a papal legate on numerous diplomatic missions across Europe and the Levant, including efforts to mediate between Venice and Genoa. Holding several high-ranking positions, he eventually became the Latin Patriarch of Constantinople and Archbishop of Crete, earning recognition for his active involvement in military and religious affairs in the East.