SARDICA (Serdica). — Today Sofia. It derives its name from the Thracian tribe of the Serdi (Dio Cassius, LI, 25). In the administrative organization given by Trajan to the Dacian region after its conquest, it took the name of Ulpia Serdica.
From the 3rd century it was assigned to Lower Dacia. After being sacked by Attila, it was subsequently provided by Justinian with fortifications, whose ruins remain, for the defense of the territory (Procopius, De Jed., 4, 1; 4, 4). Given its position in the great Illyricum, on the boundary between the western and eastern portions of the Empire, it was, like the entire Danubian region, the site of legionary formations recruited locally. Many imperial constitutions collected in the Theodosian Code are dated from S. The two emperors Galerius and Maximinus Daia were natives of S.
The Council of S. — A Synod was held, most probably in 343 (Mansi and Hefele-Leclercq place it in 344, E. Schwartz in 342), summoned by Constans I and Constantius II on the initiative of Pope Julius I. Approximately 180 bishops attended, including about 80 Eastern bishops adhering to Semi-Arianism. Hosius of Cordova presided, assisted by the papal legates, the priests Archidamus and Philoxenus. The Synod was an energetic reaffirmation of Nicene orthodoxy against the spread of Semi-Arianism.
The Semi-Arian bishops, taking advantage of the presence at the Synod of s. Athanasius, Marcellus of Ancyra, and Asclepas of Gaza, whom they regarded as deposed, formed not far from S. a conciliabulum that excommunicated Pope Julius, Hosius, and others, and promulgated a new dogmatic formula linked to the fourth Antiochene formula of 341.
The legitimate Council of S., on the other hand, reaffirmed the orthodoxy and legitimacy of s. Athanasius, Asclepas, and Marcellus; deposed certain Semi-Arian bishops, such as Theodore of Heraclea and Basil of Ancyra; reaffirmed the Nicene Creed after setting aside the proposal for a new one; established the date of Easter for the following 50 years; and promulgated 20 disciplinary canons. These regulate episcopal rights. Canons 3–5 are of particular importance: in them, the bishop of Rome is recognized as having the right to annul decrees issued against a bishop by a provincial synod and to appoint new judges to review the case. The Westerners associated the canons of S. with those of Nicaea, which gave rise to the misconception concerning their origin. The Council of S. did not succeed in restoring harmony; it did, however, at that time galvanize the orthodoxy of the West and make it evident to the scarcely orthodox Constantius II.