Jean du Tillet (Angoulême ?-1570), son of a mayor and captain of Angoulême under Francis I of France, was appointed bishop of St. Brieuc in 1553, in which capacity he took part in the Council of Trent where he encouraged Gentian Hervet to undertake a Latin translation of Photius' Syntagma together with Balsamon's interpretation from a manuscript which had recently come into his possession. Tillet also in 1553 obtained in Rome a Hebrew version of St. Matthew's Gospel. In 1564 he became bishop of Meaux, the fifteenth known John to hold that see.
Suspected of Protestant affinities, Jean du Tillet published three anti-Protestant tracts in 1563, i.e.: Traité de l'antiquité et solennité de la messe; Réponse d'un évêque aux ministres des églises nouvelles; and Avis à Messieurs les gentilhommes séduits par les piperies des églises nouvelles.
A brother, also named Jean, sieur de la Bussière, established what became a hereditary charge as greffier of the Parlement of Paris. Another brother, Louis, curé of Claix and archdeacon of Angoulême, entertained Jean Calvin.