Deira was a kingdom in Northern England during the 6th century AD. It extended from the Humber to the Tees, and from the sea to the western edge of the Vale of York. It later merged with the kingdom of Bernicia to the north to form the kingdom of Northumbria. The name of the kingdom's of Brythonic origin, perhaps from Deifr, meaning "waters", or from Daru, meaning "oak", in which case it'd mean "the people of the Derwent", a derivation also found in the Latin name for Malton, Derventio. Accordi… (More on Deira)