|Place of birth||West Point, New York|
|Allegiance||United States of America|
Rear Admiral (post retirement)
Rear Admiral Alfred Thayer Mahan (September 27, 1840 - December 1, 1914) was a United States Navy officer, geostrategist, and educator. Several ships were named USS Mahan, including the lead vessel of a class of destroyers.
Born at West Point, New York to Dennis Hart Mahan (a professor at the United States Military Academy) and Mary Helena Mahan, he attended Columbia for two years where he was a member of the Philolexian Society debating club and then, against his parents' wishes, transferred to the Naval Academy, where he graduated second in his class in 1859.
Commissioned as a Lieutenant in 1861, Mahan served the Union in the American Civil War as an officer on Congress, Pocahontas, and James Adger, and as an instructor at the Naval Academy. In 1865 he was promoted to Lieutenant Commander, and then to Commander (1872), and Captain (1885).
Despite his success in the Navy, his skills in actual command of a ship were not exemplary; and a number of vessels under his command were involved in collisions, with both moving and stationary objects.
He was appointed president of the new United States Naval War College from 22 June, 1886 to January 12, 1889 and again from July 22, 1892 to May 10, 1893 . Whilst there in 1887 he met and befriended a young visiting lecturer named Theodore Roosevelt. During this period Mahan organized his lectures into his most influential books, The Influence of Sea Power upon History, 1660-1783, and The Influence of Sea Power upon the French Revolution and Empire, 1793-1812, published 1890 and 1892, respectively.
The books' premise was that in the contests between France and England in the 18th century, domination of the sea via naval power was the deciding factor in the outcome, and therefore, that control of seaborne commerce was critical to domination in war. To a modern reader this may seem obvious and repeatedly demonstrated, but the notion was much more radical in Mahan's time, especially in a nation entirely obsessed with landward expansion to the west. After the Civil War, the United States Navy ideologically opposed the transformation of its sailing vessels to those of the technologically advanced steam-powered engines. Mahan's work encouraged a technological upgrade by convincing those opposed that naval knowledge and tactics remained as necessary as ever, but that domination of the seas dictated that the speed and predictability of steam-powered engines could not be sacrificed.
His books were received with great acclaim, and closely studied in Britain and Germany, influencing their buildup of forces in the years prior to World War I. Mahan's influence sowed the seeds for events such as the naval portion of the Spanish-American War and the battles of Tsushima, Jutland and the Atlantic. His work influenced the doctrines of every major navy in the interwar period. He was translated and extensively read in Japan, and the IJN used Influence as a textbook. This strongly affected IJN conduct of the Pacific War, with emphasis on "decisive battle", even at the expense of trade protection, to such an extent it contributed to Japan's defeat.
Between 1889 and 1892 he was engaged in special service for the Bureau of Navigation, and in 1893 Mahan was appointed to command the powerful new protected cruiser Chicago on a visit to Europe, where he was received and feted. He returned to lecture at the War College and then, in 1896, he retired from active service, returning briefly to duty in 1898 to consult on naval strategy for the Spanish-American War.
Mahan continued to write voluminously and received honorary degrees from Harvard, Yale, Columbia, Dartmouth, and McGill.
He became Rear Admiral in 1906 by an act of Congress promoting all retired captains who had served in the Civil War.