Baring-Gould’s sources: Ancient Roman Martyiologies, Usuardus, Ado, &c. Modem Roman Martyrology. In Kalendars, S. Hilarus appears on different days, Feb. 20, Feb. 2i, and Sept. 10. Authorities: — Anastasius Bibliothecarius, and the letters of S. Hilarus.] Hilarus, Deacon of the Church of Rome, and representative of S. Leo at the Council of Ephesus, whose firmness during the stormy debates had resolutely upheld the orthodoxy of the Apostolic See, was called to succeed S. Leo on the throne of S. Peter, on the death of that great pontiff.

Hilarus was a Sardinian by birth; his father’s name was Crispin. Nothing is known of him till he appears as legate [an official representative sent by the pope] of the Pope with two others in the Council of Ephesus. When that council condemned S. Flavian, Hilarus fled, uttering his protest against its decisions, and writing an indignant letter to S. Pulcheria, who, however, was powerless to help the truth, save with her prayers, as the eunuch Chrysalphus ruled the weak Theodosius [name of Roman emperors; Theodosius I (379–395) made Christianity the state religion], and threw his influence into the scale in favour of Eutychianism [followers of Eutyches, who said Christ had only a divine nature; condemned at Chalcedon in 451]. [Sept. ro.

On his return to Italy, he was created an archdeacon, and on the death of S. Leo, in 461, was elected Pope. When seated on the apostolic throne, he issued a letter, addressed to the Eastern faithful, condemning Eutyches, Nestorius [Nestorius (d. c. 451), whose teaching split Christ into two persons; condemned at Ephesus in 431], and Dioscorus, and upholding the famous Tome of S. Leo. In the West he maintained, to the utmost extent, the authority which had been claimed over the churches of Gaul [roughly modern France and Belgium] and Spain.

Rusticus, Bishop of Narbonne, on his death-bed, nominated Hermes as successor to his see. This precedent of a bishop making his see, as it were, a subject of testamentary bequest, seemed dangerous, though in this case the lawful assent had been obtained from the clergy and the people. Hilarus, at the head of a synod at Rome, condemned the practice, but for the sentence of degradation, substituted the lesser punishment, the deprivation of the right to confer ordination.