After the Council of Nicæa, a.d.325, the faith of the Catholic Church was established, but a considerable time was to elapse, and the tide of heterodoxy was to ebb and flow many times before peace should finally ensue. The |conversion| of the Emperor Constantine, though not followed, till he was dying, by baptism, led not merely to the toleration but to the protection and, as it were, the |establishment| of the Christian religion. This very naturally was followed by a large influx of worldliness into the Church, and bishops began to be time-servers and courtiers. St. Ambrose, however, was not of this number, but whether in defence of the Catholic faith, of the property of the Church, or, as in his legations to Maximus, for the protection of those in peril or anxiety who sought his aid, he braved every danger, even that of death itself.
During the greater part of the life of St. Ambrose many of those in power, amongst others the empress mother Justina, were Arians. Julian, though too early to affect the actions of the bishop, apostatized to paganism, which also numbered many supporters of high station. On the other hand, the influence of St. Ambrose, exercised even with severe strictness, was all-powerful with Theodosius, known as the emperor who subdued the Arian heresy and abolished the worship of idols in the Roman Empire.
The various historical events during the lifetime of St. Ambrose will be found entered under the different years in the subjoined table; it remains only here to give some account of his burial-place.
St. Ambrose having discovered the bodies of SS. Cosmas and Damian, a.d.389, placed them under the right side of the altar in his basilica, and desired that he should be himself buried near them to the left, which was done a.d.397. In the year 835 the Archbishop of Milan, Angilbert II., caused a large porphyry sarcophagus to be made in which he laid the body of St. Ambrose between the other two under the altar. In 1864 some excavations and repairs revealed in situ a magnificent sarcophagus nearly four and a half feet in length, three in width, and nearly two in height, without the covering, placed lengthwise. Further excavations brought to view two other tombs, one to the right and one to the left, lined with marble and placed east and west, not as the sarcophagus, north and south. In the one to the left were a few pieces of money, one of Flavius Victor, one of Theodosius, with some fragments of cloth of gold and other things. These were evidently the original resting-places of St. Ambrose and of SS. Cosmas and Damian, and the sarcophagus that constructed under Lothair, a.d.835, by Angilbert.