He was the fourth child of Prince Louis of Battenberg, afterward Marquess of Milford Haven, and his wife, Princess Victoria of Hesse-Darmstadt, granddaughter of Britain’s Queen Victoria. He entered the Royal Navy in 1913 and had various naval assignments before becoming aide-de-camp to the Prince of Wales (1921). In 1922 he married Edwina Ashley (who died in 1960 in North Borneo while on tour as superintendent-in-chief of the St. John Ambulance Brigade). In 1932 he was promoted to captain and the next year qualified as an interpreter in French and German. In command of the destroyer Kelly and the 5th destroyer flotilla at the outbreak of World War II, he was appointed commander of an aircraft carrier in 1941. In April 1942 he was named chief of combined operations and became acting vice admiral and a de facto member of the chiefs of staff. From this position he was appointed supreme allied commander for Southeast Asia (1943?46), prompting complaints of nepotism against his cousin the king. He successfully conducted the campaign against Japan that led to the recapture of Burma (Myanmar). As viceroy of India (March?August 1947) he administered the transfer of power from Britain to the newly independent nations of India and Pakistan at the partition of the subcontinent that took effect at midnight Aug. 14?15, 1947. As governor-general of India (August 1947?June 1948) he then helped persuade the Indian princes to merge their states into either India or Pakistan. He was created viscount in 1946 and earl in 1947.
Mountbatten was fourth sea lord in 1950?52, commander in chief of the Mediterranean fleet in 1952?54, and first sea lord in 1955?59. He became an admiral of the fleet in 1956 and served as chief of the United Kingdom Defense Staff and chairman of the Chiefs of Staff Committee in 1959?65. He became governor (1965) and then lord lieutenant (1974) of the Isle of Wight. Mountbatten was assassinated in 1979 by Provisional Irish Republican Army terrorists who planted a bomb in his boat.
“Mountbatten (of Burma), Louis Mountbatten, 1st Earl,” Encyclopædia Britannica