Gatianus in the third century AD was the founding bishop of the see of Tours. He was one of the "seven apostles of Gaul" commissioned by Pope Fabian to evangelize in the region.

Paul of Narbonne was one of the "apostles to the Gauls". They had been sent out during the consulate of Decius and Gratus. Their mission was to Christianise Gaul after the persecutions under Emperor Decius had all but dissolved the small Christian communities. According to the hagiographies, Fabian sent out seven bishops from Rome to Gaul to preach the Gospel: Paul to Narbonne, Gatien to Tours, Trophimus to Arles, Saturnin to Toulouse, Denis to Paris, Austromoine to Clermont, and Martial to Limoges.