Translated ‘a band of guards’, further epigraphic evidence of the presence of this unit is a brick stamp bearing the letters NV from Chester-le-Street, the former Castle of Concangios Their commanding officer is a prefect, which could mean the numerus off a legion or cavalry unit. Other brick stamps found at this location bore the overprint N CON, which resolved as Numerus Concangensium . However, this wasn’t very helpful either, since it just means “the unit in Concangis”. The inscription of the only consecration altar found there dates from the year 216 AD and mentions cavalry soldiers ( EQ[uitum]). However, since it was written nearly two hundred years before the Notitia was originally compiled, it is very likely that the unit in which these soldiers served either ceased to exist by the fourth century or had long since been transferred elsewhere (assuming the altar was donated by the garrison of the fort at that time).
Notitia Dignitatum Entry
Praefectus Numeri Vigilum Concangios
“The Prefect of the Company of Watchmen from Concangis.”
Listed under the overall command of the Duke of the Britains, the above extract undoubtedly identifies the Roman garrison of Chester-le-Street at the end of the fourth century. It is possible that this unit was later moved to Vinovia (Binchester, Durham) where undated tiles have been found bearing the legend Numerus Concangensium.