The Khedive of Egypt is styled “Your Highness,” or “His
Highness;” The children of kings and queens, “Your Royal Highness,” or
“His Royal Highness;” The children of emperors, “Your Imperial
Highness,” or “His Imperial Highness.”
Till the reign of Henry VIII. the kings of England were styled “Your
Highness,” “Your Grace,” “Your Excellent Grace,” etc., or “His” etc.
More on Highness from Infoplease:
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