The regiment left the state in May, 1861 under the leadership of Col. John W. Stiles and served at Washington, DC, mustering in to federal service there in June; in several different commands until August; in the Army of the Potomac from October; in 5th Corps, from March, 1862; in 3d Corps, Army of Virginia, from June; and in 1st Corps, Army of Potomac, from September.

The regiment served again in 5th Corps, Army of Potomac, from March, 1864, and was honorably discharged and mustered out at New York City in June, 1864; men not entitled to be mustered out were transferred to the 97th Infantry.

[1] The 83rd served along the Potomac River in Maryland and at Harper's Ferry.

In the spring of 1862 the regiment was stationed near Warrenton, Virginia and along the Rappahannock River; it participated in General John Pope's Virginia campaign, losing 75 men at the Battle of Second Bull Run.

The regiment spent the winter of 1862-3 at Falmouth, Virginia, and was not threatened during Chancellorsville, but played an important part at Gettysburg in the capture of Iverson's North Carolina brigade.