Princess

Princess is a regal rank and the feminine equivalent of prince (from Latin princeps, meaning citizen). Most often, the term has been used for the consort of a prince or for the daughters of a king or sovereign prince.

Some princesses are reigning monarchs of principalities. There have been fewer instances of reigning princesses than reigning princes, as most principalities excluded women from inheriting the throne. Examples of princesses regnant have included Constance of Antioch, princess regnant of Antioch in the 12th century. As the President of France, an office for which women are eligible, is ex-officio co-Prince of Andorra, Andorra could theoretically be ruled by a co-Princess.

For many centuries, the title "princess" was not regularly used for a monarch's daughter, who, in English, might simply be called "Lady". Old English had no female equivalent of "prince", "earl", or any royal or noble title aside from queen. Royal women were simply addressed or referred to as "The Lady [Firstname]". For example, Elizabeth and Mary, daughters of Henry VIII of England were often simply referred to as "the Ladies Elizabeth and Mary". This practice, however, was not consistent. In the marriage contract between Prince George of Denmark and Anne, daughter of James I of Great Britain, Anne is referred to as "The Princess Anne".

Practice in Britain began to change in the 18th century. After the accession of George I to the British throne, the children, grandchildren, and male line great grandchildren of the British Sovereign were automatically titled "Prince or Princess of Great Britain and Ireland" and styled "Royal Highness" (in the case of children and grandchildren) or "Highness" (in the case of male line great grandchildren). Queen Victoria confirmed this practice in Letters Patent dated 30 January 1864 (the first Act of the Prerogative dealing with the princely title in general terms). On 31 December 2012, Elizabeth II issued letters patent enabling all children of the eldest son of the Prince of Wales to enjoy the princely title and style of Royal Highness, as opposed to only the eldest son.

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