Eusebius (99) , of Cremona, presbyter, a friend of St. Jerome, through whose writings he is known. He was with Jerome at Bethlehem in 393, and became the unconscious means of extending into Italy the strife concerning Origenism which had begun at Jerusalem. Epiphanius had written to John, bp. of Jerusalem, in vindication of his conduct on his recent visit to Palestine, a.d. 394. Eusebius, not knowing Greek, begged Jerome to translate it. This Jerome did in a cursory manner (ad Pammachium, Ep. 57, § 2, ed. Vall.), and the document was stolen from the cell of Eusebius by one whom Jerome believed to be in the service of Rufinus ( cont. Ruf. iii. 4). Rufinus apparently sent the translated letter to Rome, accusing Jerome of having falsified the original. Eusebius remained at Bethlehem till Easter, 398, when he was obliged to return hastily to Italy.

On arriving in Rome, he became an agent of Jerome's party in the Origenistic controversy. He lived at first on good terms with Rufinus, who, however, afterwards accused him of having come to Rome "to bark against him." Rufinus was then engaged in translating the περί ἀρχῶν of Origen for the use of his friends, leaving out some of the most objectionable passages. Eusebius sent a copy of this to Bethlehem, where Jerome denounced it as a mistranslation. Rufinus replied that Eusebius had obtained an imperfect copy, either by bribing the copyist or by other wrong means, and had also tampered with the MS. St. Jerome, however, vehemently defends his friend from these accusations ( cont. Ruf. iii. 5). Pope Anastasius being entirely ignorant of Origen and his teaching, Eusebius, together with Marcella and Pammachius, brought before him certain passages from Origen's writings (Anastasius ad Simplicianum in Jerome, Ep. 95, ed. Vall.), which so moved him that he at once condemned Origen and all his works. Eusebius being about to return to Cremona in 400, the pope charged him in the letter just quoted to Simplicianus, bp. of Milan, and he there set forth the same passages of Origen which he had laid before the pope. He was confronted, however, by Rufinus, who declared these passages to be false; and Eusebius continued his journey without having induced Simplicianus to condemn Origen. After this we hear nothing of Eusebius for some 20 years. He appears to have remained in Italy supporting Jerome's interests and corresponding with him. At the extreme end of Jerome's life we still find Eusebius writing to him and sending him books relating to the Pelagian heresy (ad Alyp. et Aug. Ep. 143), and receiving from Jerome the last of his Commentaries, that on Jeremiah ( Prol. to Comm. on Jer. in vol. iv. 833).