Was
granted leave of absence July 30, 1862, on account of ill health, and
returned to Hiram, Ohio, where he lay ill for two months. Went to
Washington on September 25, 1862, and was ordered on court-martial duty.
November 25 was assigned to the case of General Fitz John Porter. In
February, 1863, returned to duty under General Rosecrans, then in
command of the Army of the Cumberland. Rosecrans made him his chief of
staff, with responsibilities beyond those usually given to this office.
In this field Garfield's influence on the campaign in middle Tennessee
was most important. One familiar incident shows and justifies the great
influence he wielded in its counsels. Before the battle of Chickamauga,
June 24, 1863, General Rosecrans asked the written opinion of seventeen
of his generals on the advisability of an immediate advance. All others
opposed, but Garfield advised it, and his arguments were so convincing
that Rosecrans determined to seek an engagement. General Garfield wrote
out all the orders of that fateful day, September 19, excepting one, and
that one was the blunder that lost the day. Garfield volunteered to take
the news of the defeat on the right to General George H. Thomas, who
held the left of the line. It was a bold ride, under constant fire, but
he reached Thomas and gave the information that saved the Army of the
Cumberland. For this action he was made a major-general September 19,
1863--promoted for gallantry on a field that was lost. Yielded to Mr.
Lincoln's urgent request and on December 5, 1863, resigned his commission
and hastened to Washington to sit in Congress, to which he had been
chosen fifteen months before. Was offered a division in the Army of the
Cumberland by General Thomas, but yielded to the representations of the
President and Secretary Stanton that he would be more useful in the
House of Representatives. Was placed on the Committee on Military
Affairs, then the most important in Congress. In the Thirty-ninth
Congress (1865) was changed, at his own request, from the Committee on
Military Affairs to the Committee on Ways and Means. In the Fortieth
Congress (1867) was restored to the Committee on Military Affairs and
made its chairman. In the Forty-first Congress the Committee on Banking
and Currency was created and he was made its chairman. Served also on
the Select Committee on the Census and on the Committee on Rules. Was
chairman of the Committee on Appropriations in the Forty-second and