James Allen (May 5, 1843- August 31, 1913) was an Irish-born Union Army soldier during the American Civil War. He earned the Medal of Honor for bravery at the Battle of South Mountain on September 14, 1862, during the Maryland Campaign. On April 24, 1861, shortly after the outbreak of the American Civil War, James Allen enlisted in Company F of the 16th New York Infantry. Allen was discharged along with the rest of the 16th New York in May 1863, but continued to serve the Union cause as a member of the railroad service. Allen was awarded the Medal of Honor on September 11, 1890.