Let us now try to ascertain what is known with certainty of this great Christian poet, whether Irishman or not. In the "Palatine" Codex of the Vatican Library, No. 242, there is a paragraph which states that "Sedulius was a Gentile, but learned philosophy in Italy, was afterwards converted to the Lord, and baptized by the priest Macedonius, then came to Arcadia, or according to other MSS., Achaia, where he composed this book," that is his _Carmen Paschale_. In the Vatican Codex, No. 333, probably of the eleventh century, it is added that "St. Jerome, in his Catalogue of Ecclesiastical Writers, says that Sedulius was at first a layman, learned philosophy in Italy, and afterwards, by the advice of Macedonius, taught heroic and other kinds of metre in Achaia; he wrote his books in the time of Valentinian and Theodosius," etc. Substantially the same statement is found in nearly all the twelve MSS. in the Vatican. The scribe attributes to St. Jerome, who died in A.D. 420, that continuation of Jerome's great Catalogue of Ecclesiastical Writers, which was really the work of Gennadius of Marseilles, who flourished in A.D. 495--the very time, as we shall see, that the writings of Sedulius were published. We find no statement of this kind about Sedulius in Gennadius' Catalogue, as actually published, but Sirmond declares that he himself saw in some copies of Gennadius, that Sedulius died during the reign of Valentinian and Theodosius the Younger, to the latter of whom, as he alleges, he had dedicated his work. We may then take it as certain that Sedulius flourished during their joint reigns, that is, at some period from A.D. 423 to 450, when Theodosius died; and in all probability Sedulius himself had died some years previously--that is, between A.D. 445 and 449. He is described as at first a layman and a Gentile, which is not at all unnatural, especially if he were a native of Ireland. There were indeed some Christians in Ireland before the time of St. Patrick, for Palladius was sent in A.D. 431, the year before the mission of St. Patrick "to the Scots who believed in Christ;"[39] but these Christians were not numerous. At the beginning of the fifth century, however, considerable intercourse, sometimes friendly, and sometimes hostile, existed between the Scots of Ireland and the natives of Roman Britain as well as of Roman Gaul. It would be very easy, therefore, for a young Irishman to join a band of his roving countrymen, and after learning Latin in the provincial schools of France or England, he would naturally in his search after philosophy, migrate to Italy, and there find the double treasure of faith and wisdom.