 Pitman served as a private in the 22nd Regiment Massachusetts Volunteer Infantry , Company H. This regiment was also named the " Henry Wilson 's Regiment " after Col. Henry Wilson , who commanded the unit in 1861 . Col. William S. Tilton was the commander during Pitman 's brief term of service . The regiment was part of the V Corps of the Army of the Potomac under the command of Major General George B. McClellan . During this period , the regiment fought in the Second Battle of Bull Run and was involved in the Maryland Campaign fighting in the Battle of Antietam , the bloodiest single @-@ day battle in American history , and the Battle of Shepherdstown . His regiment was on the march to the Battle of Fredericksburg when Pitman was captured by Confederate troops . 
 Pitman<a href='been_done' title='1'><mark></mark></a> served as a private in the 22nd Regiment Massachusetts Volunteer Infantry , Company H. This regiment was also named the " Henry Wilson <a href='null_genetive' title='2'><mark>'s</mark></a>Regiment " after Col. Henry Wilson , <a href='null_relcl' title='3'><mark>who</mark></a>commanded the unit in 1861 . Col. William S. Tilton was the commander during Pitman <a href='null_genetive' title='4'><mark>'s</mark></a>brief term of service . The regiment was part of the V Corps of the Army of the Potomac under the command of Major General George B. McClellan . During this period , the regiment fought in the Second Battle of Bull Run and was involved in the Maryland Campaign fighting in the Battle of Antietam , the bloodiest single @-@ day battle in American history , and the Battle of Shepherdstown . His regiment was on the march to the Battle of Fredericksburg when Pitman was captured by Confederate troops . 
Pitman done served as a private in the 22nd Regiment Massachusetts Volunteer Infantry , Company H. This regiment was also named da " Henry Wilson  Regiment " after Col. Henry Wilson , commanded the unit in 1861 . Col. William S. Tilton was the commander durin Pitman  brief term of service . Tdaregiment was part of the V Corps of the Army of thdaotomac under the command of Major General George B. McClellan . Ddurinthis period , thedagiment fought in the daond Battle of Bull Run and was involved in the Mdaland Campaign fightin in the Battle of Antietam , the bloodiest single @-@ day battle in American history , and the Badae of Shepherdstown . His regiment was on the march to the Battle of Fredericksburg when Pitman was captured by Confederate troops .