Michael Corcoran (September 21, 1827 – December 22, 1863) was an Irish-born American general in the Union Army during the American Civil War and a close confidant of President Abraham Lincoln. As its colonel, he led the 69th New York Regiment to Washington, D.C. and was one of the first to serve in the defense of Washington by building Fort Corcoran. He then led the 69th into action at the First Battle of Bull Run. After promotion to brigadier general, he left the 69th and formed the Corcoran Legion, consisting of at least five other New York regiments.
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