Forced conversions and expulsions ordered by bishops Théodore, Ferréol and Sulpice; Grégoire the Great protests against forced baptisms

Three bishops of Gaul undertook, within a few years of one another, to eliminate the Jewish communities of their cities through baptism. At Clermont, Avit had set the example; at Uzès, Ferréol left the choice between conversion and departure; at Bourges, Sulpice acted likewise; at Marseille, the bishop Théodore saw Jews driven out from elsewhere flock to him and had them baptized en masse.

Gregory the Great, informed from Rome, wrote a letter to the bishop of Marseille and to that of Arles that has remained famous: one gains nothing, he said, by bringing to baptism through coercion those who do not come through persuasion, for they return to their vomit. The principle he laid down — no forced baptism, but no new rights either — became the canonical doctrine of the Latin Church for the centuries that followed.

It was not always heeded. But it was to this correspondence that the popes of the Middle Ages turned, each time they wished to protect communities.