My general plan now was to concentrate all the force possible against the Confederate armies in the field. There were but two such, as we have seen, east of the Mississippi river, and facing north. The Army of Northern Virginia, General Robert E. Lee commanding, was on the south bank of the Rapidan, confronting the Army of the Potomac. The second, under Joseph E. Johnston, was at Dalton, Ga., opposed to Sherman, who was still at Chattanooga. Beside these main armies the Confederates had to guard the Shenandoah valley, a great storehouse to feed their armies from, and their line of communications from Richmond to Tennessee. Forrest, a brave and intrepid cavalry general, was in the West with a large force, making a larger command necessary to hold what we had gained in middle and west Tennessee. We could not abandon any territory north of the line held by the enemy, because it would lay the Northern states open to invasion. But as the Army of the Potomac was the principal garrison for the protection of Washington, even while it was moving on Lee, so all the forces to the west and the Army of the James guarded their special trusts when advancing from them, as well as when remaining at them. * * * * * Accordingly I arranged for a simultaneous movement all along the line. Sherman was to move from Chattanooga, Johnston and Atlanta being his objective points. Crooke, commanding in West Virginia, was to move from the mouth of the Gauley river, with a cavalry force and some artillery, the Virginia and Tennessee railroad to be his objective. Sigel was in command in the Valley of Virginia. He was to advance up the Valley, covering the North from an invasion through that channel, as well by advancing as by remaining near Harper's Ferry. Every mile he advanced also, gave us possession of stores on which Lee relied. Butler was to advance by the James River, having Richmond and Petersburg as his objective. * * * * * Banks, in the department of the Gulf, was ordered to assemble all the troops he had at New Orleans in time to join in the general move, Mobile to be his objective. Now for the first time in the entire history of the war a single masterful mind was in control of all the operations of all the vast armies of the United States, and was trying to direct all those operations with singleness of purpose to a foreordained end. The coming of Grant into command thus marks an epoch in the history of the war.