While bishop of Lyons, from A.D. 177 to 202, he employed the five-and-twenty years in propagating the Christian faith in Gaul, and in defending, by his writings, the Christian doctrines against the discord to which they had already been subjected in the East, and which was beginning to penetrate the West. In 202, during the persecution instituted by Septimius Severus, St. Irenæus crowned by martyrdom his active and influential life. It was in his episcopate that there began what may be called the swarm of Christian missionaries who, toward the end of the second and during the third century, spread over the whole of Gaul, preaching the faith and forming churches. Some went from Lyons at the instigation of St. Irenæus; others from Rome, especially under the pontificate of Pope St. Fabian, himself martyred in 249; St. Felix and St. Fortunatus to Valence, St. Ferréol to Besançon, St. Marcellus to Châlons-sur-Saône, St. Benignus to Dijon, St. Trophimus to Arles, St. Paul to Narbonne, St. Saturninus to Toulouse, St. Martial to Limoges, St. Andéol and St. Privatus to the Cévennes, St. Austremoine to Clermont-Ferrand, St. Galian to Tours, St. Denis to Paris, and so many others that their names are scarcely known beyond the pages of erudite historians, or the very spots where they preached, struggled, and conquered, often at the price of their lives. Such were the founders of the faith and of the Christian Church in France. At the commencement of the fourth century their work was, if not accomplished, at any rate triumphant; and when, A.D. 312, Constantine declared himself a Christian, he confirmed the fact of the conquest of the Roman world, and of Gaul in particular, by Christianity. No doubt the majority of the inhabitants were not as yet Christians; but it was clear that the Christians were in the ascendant and had command of the future. Of the two grand elements which were to meet together on the ruins of Roman society, for the formation of modern society, the moral element, the Christian religion, had already taken possession of souls; the devastated territory awaited the coming of new peoples, known to history under the general name of Germans, whom the Romans called the Barbarians. BEGINNING OF ROME'S DECLINE: COMMODUS A.D. 180 EDWARD GIBBON