Saint Gallicanus was a probably legendary Roman martyr in Egypt in 363, during the reign of Julian. According to his "Acta" (in Acta SS., June, VII, 31), which are not very reliable, he was a distinguished general in the war against the Persians. He was also consul with Symmachus in 330 and perhaps also once before with Caesonius Bassus in 317. After his conversion to Christianity he retired to Ostia, founded a hospital and endowed a church built by Constantine I. Under Julian he was banished to Egypt, and lived with the hermits in the desert. A small church was built in his honour in the Trastevere of Rome. His relics are at Rome in the church of Sant'Andrea della Valle. The legend of his conversion was dramatized in the tenth century by the nun Roswitha. He is commemorated on 25 June.