Mountbatten-Windsor

Mountbatten-Windsor is the personal surname of some of the descendants of Queen Elizabeth II and Prince Philip, Duke of Edinburgh under a Declaration made in Council in 1960. However, although the declaration specifically applies the name "Mountbatten-Windsor" to male-line descendants of the Queen not holding Royal styles and titles, "Mountbatten-Windsor" has been used by some descendants of the Queen who do hold Royal styles. This is presumably on the basis that the 1960 declaration is argued to confer a "hidden surname" in such cases. For example, Prince Andrew, Duke of York and Princess Anne, Princess Royal, children of the Queen, used the surname "Mountbatten-Windsor" in official marriage registry entries. Likewise, the Duke of Cambridge used the name when filing a French lawsuit related to the topless pictures of his wife published by the French magazine Closer.

Mountbatten-Windsor differs from the official name of the British royal family or Royal House, which remains Windsor. The adoption of the Mountbatten-Windsor surname applies only to members of the British royal family who are descended from the Queen, and not, for example, to her cousins, or descendants of her sister, Princess Margaret.

Mountbatten-Windsor may be considered a cadet branch of the House of Schleswig-Holstein-Sonderburg-Glücksburg, which in turn is a branch of the House of Oldenburg.

The Mountbatten surname derives from the German town of Battenberg, in Hesse. Prince Louis of Battenberg Anglicised his surname to Mountbatten (its literal English translation) during the First World War at the request of King George V.

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