We learn much as to these magistrates from the large number of inscriptions that have been found (over 2000 in Ostia and Portus taken together) and also as to the cults.
Vulcan was the most important - perhaps in early times the only - deity worshipped at Ostia, and the priesthood of Vulcan was held sometimes by Roman senators.
No traces of Jewish worship have been found at Ostia, but at Portus a considerable number of Jewish inscriptions in Greek have come to light.
Of the church in Ostia there is no authentic record before the 4th century A.D., though there are several Christian inscriptions of an earlier date; but the first bishop of Ostia of whom we have any certain knowledge dates from A.D.
Until Trajan formed the port of Centumcellae (Civitavecchia) Ostia was the best harbour along the low sandy coast of central Italy between Monte Argentario and Monte Circeo.