...as in the political entity that formed upon the ascension of James, already King of Scotland, to the throne of England and Wales as well thus creating Great Britain - the kingdom consisting of a unified Albany, Cambria, and Loegria located on the island of Britannia, or Britanniae Major as the latins called it - the home of the Britons.
Wrong again. James I of England (aka James VI of Scotland, prior to uniting the kingdoms) clearly was referring to the island. I would quote much more from "The Later Stuarts" volume of the Oxford History of England series, but your mind is closed, so there is not much point.