The Marquess of Milford Haven
|Born||Prince George of Battenberg|
6 November 1892 
New Palace, Darmstadt, Grand Duchy of Hesse, German Empire
|Died||8 April 1938 (aged 45)|
|Buried||13 April 1938|
Bray, Berkshire, England
( m. 1916)
|Father||Louis Mountbatten, 1st Marquess of Milford Haven|
|Mother||Princess Victoria of Hesse and by Rhine|
|Years of service||1904–37|
|Battles/wars||First World War|
Captain George Louis Victor Henry Serge Mountbatten, 2nd Marquess of Milford Haven, (6 November 1892  – 8 April 1938), born Prince George of Battenberg, styled Earl of Medina between 1917 and 1921, was a Royal Navy officer and the elder son of Louis Mountbatten, 1st Marquess of Milford Haven (Prince Louis of Battenberg), and Princess Victoria of Hesse and by Rhine.
Prince George of Battenberg, as he then was, was born at Darmstadt in the Grand Duchy of Hesse, then ruled by his maternal uncle Ernest Louis, Grand Duke of Hesse. From birth, he was a prince of the Hessian royal family, albeit of a morganatic branch. His siblings were Princess Alice (mother of Prince Philip, Duke of Edinburgh, to whom he was a mentor in Philip's adolescence), Queen Louise of Sweden and Louis Mountbatten, 1st Earl Mountbatten of Burma (who assumed the role of Philip's mentor after George's death).
George followed his father into the Royal Navy, and after passing out from the Royal Naval College at Dartmouth, was promoted to sub-lieutenant on 15 January 1913.  He was promoted to lieutenant on 15 February 1914,  and served in the First World War. In 1917, his father and several of his relations relinquished their German names, styles and titles in exchange for British peerages at the behest of George V. Accordingly, Prince George dropped the style of Serene Highness and his surname was anglicised to "Mountbatten." When his father was created Marquess of Milford Haven in late 1917, George received the courtesy title of Earl of Medina, succeeding to his father's peerage after his death in September 1921. During the war, George's aunt Empress Alexandra of Russia along with his uncle by marriage Nicholas II of Russia, five cousins and another aunt Elisabeth were killed by communist revolutionaries.
Lord Milford Haven, as George was now known, remained in the Royal Navy after the war; he was promoted to lieutenant-commander on 15 February 1922  and to commander on 31 December 1926.  In 1932, he retired from active service at his own request, with effect from 9 December of that year.  On 6 November 1937, shortly before his death, he was promoted to the rank of captain on the retired list. 
An accomplished mathematician, the Marquess "could work out complicated gunnery problems in his head" and "read books on calculus casually on trains".  Queen Elizabeth II, his niece-in-law, considered him "one of the most intelligent and brilliant of people". 
Prince George of Battenberg, as he then was known, married Countess Nadejda Mikhailovna de Torby (daughter of Russian Grand Duke Michael Mikhailovich Romanov and his morganatic wife, Countess Sophie von Merenberg) on 15 November 1916 at the Russian Embassy, Welbeck Street, London. They lived at Lynden Manor  at Holyport in Berkshire and had two children:
|Ancestors of George Mountbatten, 2nd Marquess of Milford Haven|