The 34th Illinois Infantry was organized at Camp Butler, Illinois and mustered into Federal service on September 7, 1861, and moved October 2 to Columbus, Ohio, thence to Lexington, Kentucky, and then to Camp Nevin, Kentucky, where it remained until February 14, 1862.

It was then in Kirk's brigade of Rousseau's division, marched to Bowling Green, and thence via Nashville, Franklin and Columbia, to Savannah on the Tennessee River.

It fought at the Battle of Shiloh, being then in McCook's brigade of Buell's army, losing fifteen killed, and one hundred and twelve wounded.

It was later assigned to the 2nd Brigade, 2nd Division, McCook's corps, afterward to the 14th Corps, Army of the Cumberland, participating in the following engagements: Siege of Corinth, Mississippi; Lavergne, Knob Gap or Nolensville, Stone River or Murfreesboro, Triune and Liberty Gap, Tennessee; Chickamauga, Graysville, Rocky Face Ridge, Resaca, Rome, Dallas or New Hope Church, Lost Mountain, Kennesaw Mountain, Peach Tree Creek, Siege of Atlanta, Jonesboro, and March to the Sea, Georgia; Campaign of the Carolinas, including Averasboro, Bentonville, North Carolina; and a number of minor engagements and skirmishes.

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