Titles and Style Conventions
The style His Majesty or Her Majesty (HM) is enjoyed by a King, a Queen (regnant), a Queen consort, and a former Queen consort (a Queen Dowager or a Queen Mother).
Use of the style His Royal Highness or Her Royal Highness (HRH) and the titular dignity of Prince or Princess is governed by Letters Patent issued by King George V on 30 November1917 (published in the London Gazette on 11 December 1917). These Letters Patent state that henceforth, only the children of the Sovereign, the children of the sons of the Sovereign, and the eldest son of the eldest son of The Prince of Wales would "have and at all times hold and enjoy the style, title or attribute of Royal Highness with their titular dignity of Prince or Princess prefixed to their respective Christian names or with their other titles of honour." They further state, "the grandchildren of the sons of any such Sovereign in the direct male line (save only the eldest living son of the eldest son of the Prince of Wales) shall have the style and title enjoyed by the children of Dukes."
Under these conventions, The Queen's children and the children of The Prince of Wales and The Duke of York are titled Princes or Princesses and styled Royal Highness. Likewise, The Duke of Gloucester, The Duke of Kent, Princess Alexandra, the Hon. Lady Oglivy, and Prince Michael of Kent enjoy the titular dignity of Prince or Princess and the style Royal Highness as male-line grandchildren of King George V. However, none of their children have royal titles. For example, the children of Prince Michael of Kent are known as Lord Frederick Windsor and Lady Gabriella Windsor (the courtesy titles as children of dukes), instead of HRH Prince Frederick and HRH Princess Gabriella, respectively. The children of The Princess Royal, Princess Alexandra, and the late Princess Margaret, Countess of Snowden, are not Royal Highnesses, since princesses do not normally trasmit their titles to their children. Princess Margaret's son enjoys the courtesy title Viscount Linley as the son and heir of the Earl of Snowden, while her daughter enjoys the courtsey title Lady. The children of the Princess Royal and Princess Alexandra have no titles, because Captain Mark Philips and Sir Angus Oglivy do not hold hereditary peerages.
Women marrying sons and male-line grandsons of a Sovereign are normally styled Her Royal Highness followed by the feminized version of her husband's highest title. The wives of royal peers are known as "HRH The Duchess of ..." or " HRH The Countess of ..." Thus, the wives of the Duke of Kent, the Duke of Gloucester, and the Earl of Wessex are "HRH The Duchess of Kent," "HRH The Duchess of Gloucester," and "HRH The Countess of Wessex," respectively. Before her divorce, the late Diana, Princess of Wales enjoyed the title and style of "HRH The Princess of Wales." However, when a women marries a prince who does not hold a peerage, she is known as HRH Princess [Her husband's Christian name], followed by whatever territorial or titular designation. For example, the former Baroness Marie-Christine von Reibnitz enjoys the title and style of "HRH Princess Michael of Kent," instead of "HRH Princess Marie-Christine of Kent." Similarly, the former Birgitte Eva van Deurs was titled "HRH Princess Richard of Gloucester" from her wedding day until her husband succeeded to his father's dukedom in 1974. The widows of princes remain HRH. However, under Queen Elizabeth II's 21 August 1996 Letters Patent, a divorced wife of a Prince of the United Kingdom of Great Britain and Ireland "shall not be entitled to hold and enjoy the style, title or attribute of Royal Highness."
There has been one exception to the convention that wives of princes take their husband's rank. In Letters Patent dated 28 May 1937, King George VI specifically denied the style HRH to the wife of the Duke of Windsor, the former King Edward VIII. Therefore, the former Wallis Warfield Simpson was known as "Her Grace The Duchess of Windsor," not "Her Royal Highness The Duchess of Windsor."
The daughters and male-line granddaughters of the Sovereign do not lose their royal titles upon marriage. Men who marry the daughters and the male-line granddaughters of the Sovereign, however, do not acquire their wives' royal rank and the style HRH. The only exception to this convention is Prince Philip (then-Lieutenant Philip Mountbatten, RN), who was granted the style HRH by King George VI's Letters Patent of 19 November 1947. The following day, the King created his new son-in-law Duke of Edinburgh in the peerage of the United Kingdom. The Duke of Edinburgh was expressly created a Prince of the United Kingdom of Great Britain and Northern Ireland by Queen Elizabeth II on 24 February 1947.
As grandchildren of the Sovereign through the female line, the children of the- then Princess Elizabeth and The Duke of Edinburgh would not have been entitled to use HRH or Prince or Princess until their mother became Queen, had those titles and styles not been granted in Letters Patent of 22 October 1948.
Finally, on the wedding day of HRH The Earl of Wessex to the then Miss Sophie Rhys-Jones, Buckingham Palace announced that, with the couple's agreement, any children they have should not be given the style His or Her Royal Highness, but would have courtesy titles as sons or daughters of an earl. This announcement has created considerable confusion. Since 1714, all legitimate children and legitimate male-line grandchildren of the British Sovereign have been titled Prince or Princess and styled Royal Highness. To date, the Queen has not issued Letters Patent that supersede George V's Letters Patent of 20 November 1917. Nor has the Queen issued a Royal Warrant specifically allowing the children of the Earl and Countess of Wessex (or the Earl and Countess on their behalf) to relinquish the titular dignity of Prince or Princess of the United Kingdom of Great Britain and Northern Ireland and the style Royal Highness and assume the courstey titles of an earl's children. HRH The Countess of Wessex gave birth to a daughter on 8 November 2003. The press secretary to the Queen announced that the infant would be styled the Lady Louise Windsor. Legally, however, child is HRH Princess Louise of Wessex until a Royal Warrant or Letters Patent to the contrary appear.
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