The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 3: The Decisive Battles.
Francis Trevelyan Miller, Ed.

[18] under siege. The junction of the armies of the James and of the Potomac now took place, and from this time on they together formed the left wing of the Union armies. The column in the Shenandoah valley had penetrated to near Staunton and Lynchburg, in Virginia; but their ammunition becoming almost exhausted, especially that for artillery, the army had to move over the mountains toward the Kanawha valley, thus leaving the Shenandoah valley open for General Early to pass through in making raids on the North; while the right wing of the Union army pushed its way on through northern Georgia to the Chattahoochee River, which it crossed, and moved toward Atlanta. The first phase of the great campaign was thus ended, and the second phase now opens before us.

As already described, the Shenandoah valley was left open to raids by Southern troops into the North, and so able a man as General Lee did not miss such an opportunity. A portion of the Confederates within the strong entrenchments of Petersburg and Richmond were detached under General Early, who marched down the Shenandoah, crossed the Potomac, and entered Maryland, penetrating as far as Washington, for the defense of which city two corps were detached from the right wing. They succeeded in saving the national capital and in driving Early's forces to the north and west, and took up the line of the Monocacy. Sheridan was given the command of the Federal defense. He soon placed himself in the valley of the Shenandoah, where his army now became the center of the Union line.

The second phase was the adoption of the policy to keep the Confederate armies within the besieged cities, Richmond, Petersburg, and Atlanta, and actively to engage the outside troops, to drive all the smaller bands to the south, to devastate the country from which supplies were drawn, and, as far as possible, to destroy the troops that gathered these supplies. In these movements the most active and most effective column was the Army of the Shenandoah, which soon sent the opposing