Corps badges in the American Civil War were originally worn by soldiers of the Union Army on the top of their army forage cap (kepi), left side of the hat, or over their left breast. The idea is attributed to Maj. Gen. Philip Kearny, who ordered the men in his division to sew a two-inch square of red cloth on their hats to avoid confusion on the battlefield. This idea was adopted by Maj. Gen. Joseph Hooker after he assumed command of the Army of the Potomac, so any soldier could be identified at a distance. For Army corps that had more than three divisions, the standardization was lost: