Dixon S. Miles, born in Maryland in 1804, was admitted to West Point in the summer of 1819, at the age of 15.  Among his classmates were Dennis Hart Mahan - the legendary West Point instructor - who ranked first in the class.  At his graduation in 1824, Miles ranked 27th in a class of 31, and was assigned to the infantry.  His first assigment was Bvt. Second Lieut., 4th Infantry, July 1, 1824, and Second Lieut., 7th Infantry, July 1, 1824..  After serving as adjutant for five years, he was commissioned as captain, 8 June, 1836, and held a staff appointment as quartermaster during the Florida war and until the beginning of the war with Mexico. 

During the War with Mexico, he was engaged in the Defense of Ft. Brown, May 3-9, 1846.  He was brevetted. Major, May 9, 1846, for Gallant and Distinguished Conduct in the Defense of Ft. Brown, Tex.  He was engaged in the Battle of Monterey Sep. 21-23, 1846, and the Siege of Vera Cruz, May 9-29, 1847.  Miles was given a Bvt. Lieut.-Col., Sep. 23, 1846, for Gallant and Meritorious Conduct in the Several Conflicts at Monterey, Mex..  Promoted to Major, 5th Infantry, on Feb. 16, 1847, he was in command of the City of Vera Cruz, Aug. 11 to Dec. 23, 1847.

At the close of the war, he returned to garrison at East Pascagoula, Mis., 1848, and was on frontier duty at Ft. Gibson, Indian Territory (1848) and Ft. Washita, I. T., 1849-51.  He was promoted to Lieut.-Colonel of the 3d Infantry on Apr. 15, 1851. 

During the 1850s, Miles was posted at Ft. Fillmore, N. M., 1851-53; Albuquerque, N. M., 1853; Fillmore, NM., 1854-56; and Ft. Thorn, N. M., 1856-57.  From May 1 to July 26, 1857, he was in command of the Southern column of Gila Expedition, being engaged in the combat of June 27, 1857 on Gila River, north of Mount Turnbull, NM.   Miles returned to Ft. Fillmore, N. M. 1857-58; and was in command of the Navajo Expedition, N. M., Sep.-Dec., 1858.  After another posting in Albuquerque, N. M., 1858-59; he was in garrison at St. Louis, Mo., 1859-60.

He was made colonel of the 2nd infantry on 19 January, 1859, was on duty at Ft. Kearny, Nebraska (1860-61) and Fort Leavenworth, Kansas (1861)/  After the beginning of the civil war, he was ordered to the east, taking part in the defence of Washington, and commanding the reserve at the battle of Bull Run. After several months' leave of absence, he was given charge of a brigade guarding the Baltimore and Ohio railroad in March, 1862. In September he was intrusted with the command of the post of Harper's Ferry. He asked for re-enforcemen(s, but they were not sent. After Maryland heights had been evacuated by the force that was posted there, and when the enemy opened fire from commanding positions in two quarters, he offered no further resistance, but surrendered the post with 11,500 troops and arms, ammunition, and supplies.  On Sept 16th, 1862, Col. Dixon Miles was mortally wounded by a piece of shell at Harper's Ferry and died shortly afterwards.