Anastasius Bibliothecarius, librarian of the Roman Church, b. about 810; d. 879. He was a nephew of Bishop Arsenius of Orta, who executed important commissions as papal legate. Anastasius learned Greek from Greek monks, and obtained an unusual education for his era, so that he appears to be the most learned ecclesiastic of Rome in the barbaric period of the ninth century. During the reign of Nicholas I (855-67) Anastasius was abbot of the monastery of the Virgin Mary on the farther side of the Tiber (in Trastevere), and he was employed by the pope in various matters. He was also active as an author, and translated Greek works into Latin, one of these being the biography of St. John the Almsgiver, which he dedicated to Nicholas I. The successor of Nicholas, Adrian II (867-72), appointed Anastasius librarian of the Roman Church, an important office which gave him much influence at the papal Court. In 869 he was sent by Emperor Louis II as envoy to Constantinople, with two men of high rank in the Frankish Empire, to negotiate a marriage between the oldest son of the Byzantine emperor and the daughter of the emperor in the West. When the envoys arrived at Constantinople the Eighth Ecumenical Council was still in session, and Anastasius, who attended the last session (February 870), zealously defended the papal cause and was of much service to the papal legates. On their way home the papal legates were robbed, and the “Acts” of the council were carried off. However, they had given most of the declarations of obedience of the Greek bishops to Anastasius, who also had a copy of the “Acts”, and was thus able to bring these documents to the pope. At the pope’s order he translated the “Acts” into Latin. The succeeding pope, John VIII (872-82), also esteemed Anastasius, confirmed him in the office of librarian, entrusted important affairs to him, and encouraged him to further literary work. Anastasius was in correspondence with the deposed Byzantine patriarch, Photius, and sought to mediate between the patriarch and the pope and also to assuage the controversy over the Holy Ghost by assuming that the Latins understood the procession (processio) of the Holy Ghost from the Son in the sense of transmission (missio).
If a passage in the annals of Hincmar of Reims is genuine (Mon. Germ. Hist.: Scriptores, I, 447) and Hincmar has not confused two men, then the librarian Anastasius is identical with the Roman presbyter Anastasius who in 874 became titular priest of St. Marcellus, and in 848 fled from Rome, and resided in various cities. On account of his flight he was excommunicated by a Roman synod in 850, and, as he did not return, was anathematized and deposed by another synod in 853. After the death of Leo IV in 855 this Anastasius was elected as antipope by the imperial party, but the rightfully elected pope Benedict III, gained the supremacy, and acted kindly towards the usurper. During the pontificate of Adrian II Anastasius became involved in serious difficulties, in 868 a near relative of his named Eleutherius forcibly carried off the daughter of the pope, and soon after killed both her and her mother. The murderer was executed and Anastasius, who was regarded as the instigator of the murder, was punished by excommunication and deposition. He lived at the imperial Court, and sought by the intervention of the emperor to exculpate himself before the pope. Hergenröther (Photius, II, 230-240) maintains, with good reason, that the librarian and the presbyter Anastasius (the antipope) were one and the same person, and weaves all the statements concerning the latter into the biography of Anastasius, while Langen (Geschichte der römischen Kirche. III, 270 sqq.) considers them different persons. In August, 879, Zacharias of Anagni appears as librarian of the Roman Church, so that Anastasius must have died shortly before this date.
Anastasius translated from Greek into Latin the “Acts” of the Seventh and Eighth Oecumenical Councils, as well as several legends of saints, and other writings. He also compiled a historical work, “Chronographia tripartita”, from the Greek writings of Theophanes, Nicephorus, and Syncellus, and made a collection of documents concerning the affairs of Pope Honorius. Several important letters written by him have been preserved. His writings are to be found in P.G., XXIX; P.L., LXXIII, CXXII, CXXIX. The “Liber Pontificalis“, which was formerly ascribed to him, was not written by him; he seems to have shared in the revision of the “Life” of Nicholas I.
J. P. KIRSCH