The committee was dominated by Radical Republicans whose aggressive views often clashed with the strategies favored by President Abraham Lincoln.
It was established on December 9, 1861, following the Union defeat at the Battle of Ball's Bluff, at the instigation of Senator Zachariah T. Chandler.
Its purpose was to investigate such matters as illicit trade with the Confederate States, medical treatment of wounded soldiers, military contracts, and the causes of Union battle losses.
The committee was also involved in supporting the war effort through various means, including endorsing emancipation of slaves, the use of black soldiers, and the appointment of generals known to be aggressive fighters.
Chairman Benjamin Wade and key leaders were Radical Republicans, who wanted more aggressive war policies than those of Lincoln.
One of the most colorful series of committee hearings followed the Battle of Gettysburg in 1863, when Union Maj. Gen. Daniel Sickles, a former Representative, accused Maj. Gen. George G. Meade of mismanaging the battle, planning to retreat from Gettysburg before his victory there, and failing to pursue and defeat Robert E. Lee's army as it retreated.
Bill Hyde notes that the committee's report on Gettysburg was edited by Wade in ways that were unfavorable to Meade, and the evidence was even distorted.
The first presented reports and testimony taken involving the alleged Confederate mistreatment of United States Colored Troops soldiers after their surrender at Fort Pillow.
Extensive testimony was taken on ordnance, contracts to supply ice for the war effort, turreted Monitor-class warships, and the massacre of friendly Cheyenne Indians at Sand Creek, Colorado.
[10] Tap finds that "the committee's investigations, its leaks to the press, and its use of secret testimony to discredit generals such as McClellan certainly were instrumental in creating hostility between the army's West Point officers and the nation's civilian leaders."
Finally, because of its collective ignorance of military science and preference for the heroic saber charge, "the committee tended to reinforce the unrealistic and simplistic notions of warfare that prevailed in the popular mind," writes Tap.