Silas Colgrove was the typical "old-fashioned Colonel" of the American Army. At times, brave and courageous to a fault; at others, careful and judicious to an admirable degree. He was always kind and cheerful to his men, winning not only their admiration and respect, but their love and confidence. His stanch, soldierly virtues were largely reflected in his men, making the Twenty-seventh a reliable and hard fighting regiment. That it faced unflinchingly the musketry of many fields is clearly indicated in its extraordinary percentage of loss. It left the State September 15, 1861, and soon after its arrival at Washington was assigned to Banks's command. It wintered near Frederick, Md., and in the spring participated in Banks's Shenandoah campaign. After that, its history is identical with that of the Twelfth Corps and Williams's Division.
Its casualties in battle were severe, especially in proportion to its numbers. It lost at Cedar Mountain 15 killed, 29 wounded, and 6 missing; at Antietam, 18 killed, 191 wounded, no missing; at Chancellorsville, 20 killed, 126 wounded, and 4 missing; at Gettysburg, 23 killed, 86 wounded, and 1 missing At Resaca, Ga., the regiment captured the colors and the Colonel of the Thirty-eighth Alabama, together with a large number of prisoners, Colgrove handling his men well in this fight, the loss not exceeding 68 killed and wounded, while it inflicted five times that on the enemy. In 1864 the designation of the Corps was changed to the Twentieth, although the old badges and division commanders were retained. The regiment served in the Twentieth Corps in the Atlanta campaign, after which, its term having expired, it was mustered out.