A Christian of Sardinian origin, Eusebius (d. 369–370 CE) left his homeland to pursue an ascetic way of life (Ambr. Epist.EC 14.66–68), becoming a lector at the Roman Church, before being elected the first bishop of Vercelli in the mid-340s CE (Jer. Vir. ill. 96).

Very little is known of his life until 353 CE, when he started campaigning for a synod that rehabilitated his fellow Nicene bishop Athanasius of Alexandria, who had been banished for the second time in 338 CE (Liber. Ep. 1–3). The council (Councils/Synods) was eventually celebrat…