The Arian Controversy
Julius's fifteen-year pontificate turned largely on the aftermath of the First Ecumenical Council and the struggle over Arianism. When the followers of Eusebius of Nicomedia renewed the deposition of Athanasius of Alexandria at a synod in Antioch around 341, Julius proposed that both parties present their case before a synod under his own presidency. The Eastern bishops rejected the proposal.
In autumn 340 or 341 Julius convened a synod at Rome, meeting at the titular church of the presbyter Vitus. It examined the documentary evidence and exonerated both Athanasius and Marcellus of Ancyra, restoring their episcopal rights; Athanasius was received at Rome and recognized as a legitimate bishop at a synod there in 342. Julius defended this decision in a letter to the Eastern bishops, and beyond Athanasius he also gave refuge to Paul, the bishop of Constantinople driven out by Arian-aligned factions.
The Council of Sardica and Roman Primacy
Julius's efforts contributed to the convening of the Council of Sardica in Illyria around 343–344. There the assembly divided: some seventy-six Eastern bishops withdrew to Philippopolis and issued their own deposition of Julius alongside Athanasius, while about three hundred Western bishops remained and ratified the previous Roman decisions. He sent his own representatives to the council — the priests Archidamus and Philoxenus and the deacon Leo.
The council's canons on the review of episcopal condemnations, which touched on appeals to Rome, are read by historians as advancing claims of Roman primacy. Julius's own letter to the Eastern bishops presses this theme, asserting that it was the custom for Rome to be written to first so that what was just might there be defined.
Building and Legacy
Within Rome, Julius is credited with building two basilicas: the titular church of Julius, now Santa Maria in Trastevere, and the Basilica Julia, now the Church of the Twelve Apostles. Beyond the city walls he built three cemetery churches, on the Via Portuensis, the Via Aurelia, and the Via Flaminia.
He died on 12 April 352 and was buried in the catacombs of Calepodius on the Via Aurelia, succeeded by Pope Liberius. He was quickly venerated as a saint and is commemorated in the Eastern Orthodox Church on 12 April. A later tradition crediting Julius with fixing 25 December as the official date of Christ's Nativity rests on a letter quoted only in a ninth-century source and is regarded by scholars as spurious.
Relics & Shrines
Julius was buried in the catacombs of Calepodius on the Via Aurelia, outside the walls of Rome, one of the cemetery churches associated with his own building program.
