British Emperor

Although in the past the style of British Emperor has been (retroactively) applied to a few mythical and historical rulers of Great Britain or the United Kingdom, it is sometimes used as a colloquialism to designate either Plantagenet and Tudor caesaropapism or, more frequently, the British sovereign during the period of the Raj.

The mythical British ruler King Arthur is referred to in medieval Welsh texts as ameraudur (meaning "emperor"). The Welsh poem Geraint, son of Erbin, written in the 10th or 11th century, describes a battle at a port-settlement and mentions Arthur in passing. The work is a praise-poem and elegy for the 6th-century king Geraint, provides the earliest known reference to Arthur as "emperor."

The Britannic Empire was a short-lived breakaway state of the Roman empire in the late Roman Period. It was formed as a result of the revolt by the naval commander Carausius. It ended when Carausius's usurper, Allectus, was defeated by the Emperor Constantius I in 296.

Kings of England displayed imperial ambition in the period from 930 to 1066:

In this case the epithet "Empress" was rather used to distinguish this person from other princesses called Matilda or Maud. Matilda was not Empress of Britain; she took her title from her previous marriage to Holy Roman Emperor Henry V.

Although several English monarchs flirted with the idea of "imperial" power, this never led to an official change of the title of "King/Queen" to that of "Emperor/Empress".

In Christian Europe the use of the title emperor was more than an affectation. A king recognises that the church is an equal or superior in the religious sphere; emperors do not. This was illustrated by Henry VIII of England who started to use the word imperium in his dispute with Pope Clement VII over the annulment of his first marriage. The distinction began to blur when kings began to claim divine rights.

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