Britannia

Britannia, sometimes referred to as the Empire in Britannia (Latin: Imperium in Britannia), was a feudal empire ruling over the entirety of the British isles from 1012 onwards. The Empire was the result of the conquests of the House of Thorgil, which brought the entirety of the old Roman province of Britannia south of Hadrian's Wall under the rule of the Thorgiling Kings of England. This sparked the Britannic Renaissance, a period in which the Romano-British culture in the British Isles experienced a revival and the elite became increasingly latinised. The Empire was, thus, essentially seen as the revival of the pax romana over Britain under the House of Thorgil. The official proclamation of imperium conferred on the King of England in 1012 is considered the establishment of the Empire.

Although called an Empire under modern naming conventions, it should be noted that its contemporaries did not necessarily consider Britannia an Empire (hence the title Emperor in rather than of Britannia). The prevailing conception of Empire at the time in Western Christendom was that there was but one Empire, which was the successor of the Roman Empire in the West. This title was held by the Holy Roman Empire under the principle of translatio imperii. The imperium of the Britannic Emperor, therefore, was considered a local exercise of the Roman supreme power by a single King invested with imperium, rather than a separate claim to the legacy of Rome (like in the Empire of Germania).

The legitimacy of the Britannic crown was tied in strongly to the legends of King Arthur, which were used with by the ruling Thorgilings to create an image of a unified British realm as a sort of new Camelot, taking emphasis away from their origins as Norse conquerors. The coat-of-arms and banners used by the Imperial Crown are a witness to this, bearing the red (British) and white (Anglo-Saxon) dragons of the legendary King Uther Pendragon.