URSINO, ANTIPAPA. — When Pope Liberius died (September 366), while the deacon Damasus was being canonically elected in the church of S. Lorenzo in Lucina, 7 presbyters
and 3 deacons elected the deacon U. in the « basilica Julii » (S. Maria in Trastevere), who was immediately consecrated by the bishop of Tivoli.
The schism immediately degenerated into civil war, and Rome became the scene of bloody episodes. A group of Damasus’s supporters besieged the basilica Julii for 3 days and ultimately prevailed: there were dead and wounded; U. and the 2 deacons were driven into exile. The presbyters, however, who had remained in Rome, continued to hold liturgical assemblies on their own behalf. In order to eliminate every cause for conflict, they too were arrested, but their followers rescued them from the police, and all together they occupied the Liberian Basilica. The Damasian party besieged them once again and succeeded in overcoming them in a clash in which 137 people perished. Damasus remained master of the situation and, once calm had returned, in September 367 the exiles were permitted to return. The disturbances, however, began again, and the city prefect was forced to send U. and his adherents back into exile. A group of fanatics continued to gather in the basilica of S. Agnese on the Via Nomentana; new riots arose from this, and the schismatics were then forbidden to assemble within a circuit of 20 miles from Rome. U., who in the meantime had been relegated to Cologne, obtained permission to reside in Milan, where he joined the Arians and Valens of Pettau. Although far from Rome, he did not cease causing trouble for Damasus and incited the converted Jew Isaac to bring a legal action against the Pope, who was, however, found innocent. To prevent him from causing harm, s. Ambrogio wrote to the emperor Gratian, urging him to put an end to the machinations of the schism (381). U. died shortly afterward.