Editing George Armstrong Custer (section)

===McClellan and Pleasonton===
[[File:CusterandWashington01.jpg|thumb|Custer with former classmate, friend, and captured Confederate soldier, Lieutenant James Barroll Washington, an aide to [[Joseph E. Johnston|General Johnston]], at Fair Oaks, Virginia, 1862]]
Like the other graduates, Custer was commissioned a [[US Second Lieutenant|second lieutenant]]; he was also assigned to the [[2nd Cavalry Regiment (United States)|2nd U.S. Cavalry Regiment]] and tasked with drilling volunteers in Washington, D.C. On July 21, 1861, he was with his regiment at the [[First Battle of Bull Run]] during the [[Manassas Campaign]] where Army commander [[Winfield Scott]] detailed him to carry messages to Major General [[Irvin McDowell]]. After the battle, he continued participating in the defense of Washington D.C. until October 1861, when he became ill.<!-- From what? --> He was absent from his unit until February 1862. In March, he participated with the 2nd Cavalry in the [[Peninsula Campaign]] in Virginia until April 4.

On April 5, Custer served in the [[5th Cavalry Regiment]] which participated in the [[Siege of Yorktown (1862)|Siege of Yorktown]] from April 5 to May 4 and was aide to [[Major general (United States)|Major General]] [[George B. McClellan]]. McClellan was in command of the [[Army of the Potomac]] during the Peninsula Campaign. On May 24, 1862, during pursuit of [[Confederate States Army|Confederate]] General [[Joseph E. Johnston]] up the Peninsula, General McClellan and his staff were reconnoitering a potential crossing point on the [[Chickahominy River]], they stopped, and Custer overheard General [[John G. Barnard]] mutter, "I wish I knew how deep it is." Custer dashed forward on his horse out to the middle of the river, turned to the astonished officers, and shouted triumphantly, "McClellan, that's how deep it is, General!"<ref name="tagg"/>

Custer was assigned to lead an attack with four companies of the 4th Michigan Infantry across the Chickahominy River above New Bridge. The attack was successful, resulting in the capture of 50 Confederate soldiers and the seizing of the first Confederate battle flag of the war. McClellan termed it a "very gallant affair" and congratulated Custer personally. In his role as aide-de-camp to McClellan, he began his life-long pursuit of publicity.<ref name="tagg">Tagg, Larry. (1988). ''The Generals Of Gettysburg: Appraisal Of The Leaders Of America's Greatest Battle''. Savas Publishing Company, {{ISBN|1-882810-30-9}}, p. 184.</ref> He was promoted to the rank of [[Captain (Union Army)|captain]] on June 5, 1862. On July 17, he was demoted to the rank of [[First Lieutenant]]. He participated in the [[Maryland Campaign]] in September to October, the [[Battle of South Mountain]] on September 14, the [[Battle of Antietam]] on September 17, and the March to [[Warrenton, Virginia]], in October.

[[File:Lincoln and generals at Antietam.jpg|thumb|Custer (extreme right) with [[Abraham Lincoln|President Lincoln]], General McClellan and other officers at the [[Battle of Antietam]], 1862]]

On June 9, 1863, he became aide to Brevet Lieutenant Colonel [[Alfred Pleasonton]], who was commanding the Cavalry Corps, Army of the Potomac. Recalling his service under Pleasonton, he was quoted as saying that "I do not believe a father could love his son more than General Pleasonton loves me."<ref>{{Cite book|title=Custer Victorious: The Civil War Battles of General George Armstrong Custer|last=Urwin|first=Gregory J. W|publisher=U of Nebraska Press|year=1983|isbn=0803295561|pages=[https://archive.org/details/custervictorious00urwi/page/41 41]|url=https://archive.org/details/custervictorious00urwi/page/41}}</ref> Pleasonton's first assignment was to locate the army of [[Robert E. Lee]], moving north through the [[Shenandoah Valley]] in the beginning of what was to become the [[Gettysburg Campaign]].