 It was originally a suffragan diocese of the Metropolitanate of Milan up to 1806, when it was transferred to the Metropolitanate of Aix; but it has been a suffragan of the Archdiocese of Genoa since 1818.It is probable that Ventimiglia had a bishop from the fifth century; the first known is Joannes (680).Bishop Gianfrancesco Gandolfo (1623–1633) negotiated the peace between Savoy and Genoa, which was proclaimed on 10 August 1634.