Saint Potamius

Potamius (Greek: Ποτάμιος, fl. 343–360 AD), also known as Potamius of Lisbon, was the first recorded bishop of the city of Lisbon. He was possibly born in Lisbon, given that Iberian communities at the time usually chose their own citizens as bishops. He was part of the Council of Sirmium in 357, in which he defended Arianism. He is the second earliest Christian prose writer of the Iberian Peninsula, with Hosius of Corduba being the first. The historical evidence on Christian presence in the Iberian Peninsula is scarce and lacking in detail. The Synod of Elvira attests Christian presence in Iberia somewhere between 295 and 314 and allows scholars to estimate the existence of 41 Christian communities in Iberian by the time, with Hispania Baetica and Carthaginiensis as the most Christianized provinces. Rodrigo da Cunha placed the first Christian communities in Lisbon between 36 and 106 AD and considered Potamius to be the fifth bishop (Mantius of Évora being the first), but this view failed to meet scientific rigor. The Holy Martyrs of Lisbon (303 AD), during the Diocletianic Persecution, may attest Christian presence in the beginning of the 4th Century AD, although the first documents regarding the events of the Holy Martyrs date only to the 9th Century. The Synod of Elvira mentions the presence of three Lusitanian dioceses: Ebora, Ossonoba, and Mérida. In 318 or 319, Arius had founded Arianism, denying Trinitarianism by positing that Jesus' existence was not eternal and that his substance was not equal to that of God. In 325, the Roman Emperor Constantine convened the First Council of Nicaea, led by Hosius of Corduba, in which Arianism was strongly rejected and Arius exiled by Constantine. Later, Arianism managed to regain some importance in the Roman Empire, mostly be the actions of Eusebius of Nicomedia and his (successful) attempts to exile the Nicean Athanasius of Alexandria.