The Mountbatten family is a British dynasty originating as a cadet branch of the German princely Battenberg family. The name was adopted during World War I by members of the Battenberg family residing in the United Kingdom due to rising anti-German sentiment amongst the British public. The name is a direct Anglicisation of the German Battenberg (literally Batten Mountain), a small town in Hesse. The title of count of Battenberg, later prince of Battenberg, was granted to a morganatic branch of the House of Hesse-Darmstadt, itself a cadet branch of the House of Hesse, in the mid 19th century.
The family now includes the Marquesses of Milford Haven (and formerly the Marquesses of Carisbrooke), as well as the Earls Mountbatten of Burma. Prince Philip of Greece and Denmark, the consort of Queen Elizabeth II, adopted the surname of Mountbatten from his mother's family in 1947, although he is a member of the House of Schleswig-Holstein-Sonderburg-Glücksburg by patrilineal descent. Lady Louise Mountbatten became Queen Consort of Sweden, after having married Gustaf VI Adolf of Sweden.
The Mountbatten family are a branch of the German house of Battenberg. The Battenberg family was a morganatic branch of the House of Hesse-Darmstadt, rulers of the Grand Duchy of Hesse in Germany. The first member of the House of Battenberg was Julia Hauke, whose brother-in-law Grand Duke Louis III of Hesse created her Countess of Battenberg with the style Illustrious Highness in 1851, on the occasion of her morganatic marriage to Grand Duke Louis' brother Prince Alexander of Hesse and by Rhine. Julia was elevated in her title to Princess of Battenberg with the style Serene Highness (HSH) in 1858.
Two of Alexander and Julia's sons, Prince Henry of Battenberg and Prince Louis of Battenberg, became associated with the British Royal Family. Prince Henry married The Princess Beatrice, the youngest daughter of Queen Victoria. Prince Louis married Victoria's granddaughter, Princess Victoria of Hesse and by Rhine, and became the First Sea Lord of the Royal Navy. Due to anti-German feelings prevalent in Britain during World War I, Prince Louis, his children, and his nephews (the living sons of Prince Henry), renounced their German titles and changed their name to the more English sounding Mountbatten. (They rejected an alternative translation, "Battenhill".)Their cousin, George V compensated the princes with British peerages. Prince Louis became the 1st Marquess of Milford Haven, while Prince Alexander, Prince Henry's eldest son, became the 1st Marquess of Carisbrooke.
Mountbatten-Windsor is the personal surname of some of the descendants of Queen Elizabeth II and Prince Philip, Duke of Edinburgh under an Order in Council issued in 1960, which has not been applied consistently. While the Order specifically applies the surname "Mountbatten-Windsor" to Elizabeth's male-line descendants not holding Royal styles and titles, "Mountbatten-Windsor" has been formally used by some of her descendants who do hold Royal styles. The surname was first officially used by Princess Anne in 1973, in the wedding register for her marriage to Mark Phillips. Prince William and his wife Catherine used the names "Monsieur et Madame Mountbatten-Windsor" when filing a French lawsuit against the French magazine Closer. On 8 May 2019, Prince Harry, Duke of Sussex and Meghan, Duchess of Sussex announced the name of their son to be Archie Harrison Mountbatten-Windsor.
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 Royal Family who are descended from Elizabeth, and not, for example, to her cousins, or descendants of her sister, Princess Margaret.