MARCUS, pope, saint. — He was a Roman by birth and the son of Priscus; he governed the Roman Church for about nine months, from 18 January to 7 October 336. Little is known of his deeds; he seems to have taken no part at all in the Arian controversy, the correspondence with St. Athanasius attributed to him by the Pseudo-Isidore being certainly spurious.
The *Liber Pontificalis* attributes to him the concession of the pallium and the prerogative of the bishop of Ostia to consecrate the new bishop of Rome. He built two basilicas: one in the city, the *Titulus Marci*, recently discovered during excavations; the other on the Via Ardeatina, now disappeared. His burial in the cemetery of Balbina on 7 October is recorded in the *Depositio episcoporum*; on the same date, he is commemorated in the *Martyrologium* and the *Roman Breviary*.