Arsacius of Tarsus (Greek: Ἀρσάκιος; before 324 – 11 November 405) was the intruding archbishop of Constantinople from 404 to 405, after the violent expulsion of John Chrysostom.
[1] In earlier life his brother had selected him for the bishopric of Tarsus and had attributed his refusal to an ambitious design of becoming his successor at Constantinople.
Moreover, his hostility to Chrysostom had been sufficiently testified at the synod of the Oak, when he appeared as a witness against him and vehemently pressed his condemnation.
We learn from Sozomen,[6] that Arsacius was not personally responsible for these cruel deeds; but he lacked strength of character to offer any decided opposition to the proceedings of his clergy.
The whole Western episcopate refused to acknowledge him, and Pope Innocent I, who had warmly espoused Chrysostom's interests, wrote to the clergy and laity of Constantinople strongly condemning the intrusion of Arsacius, and exhorting them to persevere in their adhesion to their true archbishop.