The British empire was one of the largest (I believe it may have been the largest) empires in history. Yet, I have only ever heard of the British monarchs referred to as a King or Queen, never an Emperor or Empress. Why is this?
British Monarchs from 1876 to 1947 were called 'of the United Kingdom of Great Britain and Ireland Queen, Defender of the Faith, Empress of India" or "of the United Kingdom of Great Britain and Ireland and of the British Dominions beyond the Seas King, Defender of the Faith, Emperor of India".
So King or Queen of the european lands and emperor/empress of india.