Eboracum over Britain. Whilst the latest datable inscription referencing "Eboracum" dates from AD237, the continuation of the settlement after this time is certain. Building work in the city continued in the fourth century under Constantine and later Count Theodosius. The locally produced Crambeck Ware pottery arrives in "Eboracum" in the fourth century – the most famous form being intricately decorated buff-yellow 'parchment ware' painted with bright shades of red. The effect of Constantine's religious policy allowed the greater development of Christianity in Roman Britain – a bishop of York named 'Eborius' is attested here and several artifacts decorated with chi-rho symbols
Deira would mean "the people of the Derwent", a derivation also found in the Latin name for Malton, "Derventio". The modern Gaelic 'Doire' (pronounced Dirruh/Durruh) is the same word. The origin of the name for County Londonderry and city of Derry stems from this word with an oak being featured on the crest of Derry GAA. According to Simeon of Durham (writing early in the 12th century), it extended from the Humber to the Tyne, but the land was waste north of the Tees. After the Brythonic kingdom centred on "Eboracum", which may have been called Ebrauc, was taken by King