Grant fixed his own headquarters with the Army of the Potomac at Culpeper Court House, north of the Rapidan. Lee's Army of Northern Virginia, was at Orange Court House, over twenty miles south. Grant, taking his own headquarters as the center, regarded Butler's Army of the James as the left wing, which could unite with the center round Richmond and Petersburg. The long right wing ran through the whole of West Virginia, Kentucky, and Tennessee, clear away to Memphis, with its own headquarters at Chattanooga. There Sherman faced Johnston, who occupied a strong position at Dalton, over thirty miles southeast. The great objectives were, of course, the two main Southern armies under Lee and Johnston, with Richmond and Atlanta as the chief positions to be gained.
All other Union forces were regarded as attacking the South from the rear. Wherever coast garrisons could help to tighten the blockade or seriously distract Confederate attention they were left to do so. Wherever they could not they were either depleted for the front or sent there bodily. The principal Union field force attacking from the rear was to have been formed by Banks's forty thousand veterans in conjunction with Farragut's fleet against Mobile. But the Red River Expedition spoilt that combination in the spring and postponed it till August, when Farragut did nearly all the fighting, and the cooperating army was far too late to produce the distracting effect that Grant had originally planned.
General Franz Sigel was sent to the upper Shenandoah Valley, both to guard that approach on Washington and to destroy the resources on which Lee's army so greatly relied. General George Crook was given a mounted column to operate from southern West Virginia against the line of rails running toward Tennessee through the lower end of the Valley.
The most notable new general was Philip H. Sheridan, whom Grant selected for the cavalry command. Sheridan was thirty-three, two years older than his Southern rival, Stuart, and, like him, a young regular officer who rose to well-earned fame the moment his first great chance occurred.
Sherman we have met from the very beginning of the war and followed throughout its course. He was continually rising to more and more responsible command; but it was only now that he became the virtual Commander-in-Chief of all the river armies and the chosen cooperator with Grant on a universal scale. He was of the old original stock, his first American ancestors having emigrated from England in 1634. An old regular, with special knowledge of the South, and in the fullness of his powers at the age of forty-four, he had developed with the war till there was no position which he could not fill to the best advantage of the service.
Grant fixed the fourth of May for the combined advance of all the converging forces of invasion. There were two weak points where the Union armies failed: one in the farthest south, where, as we have so often seen, Banks could not attack Mobile owing to his absence at Red River; the other in the farthest north, where Sigel was badly beaten and replaced by Hunter. Here, after much disabling interference at the hands of Stanton, Hunter was succeeded by Sheridan, whom Grant himself directed with consummate skill. There were also two Confederate thorns in the Federal side: Forrest's cavalry in Sherman's rear, Mosby's cavalry in Grant's. Forrest roved about the river area, snapping up small garrisons, cutting communications, and doing a good deal of damage right up to the Ohio. Mosby, with a much smaller but equally efficient force, actually raided to and fro in Grant's immediate rear; and on one occasion nearly captured Grant himself just on the eve of the opening move. As Grant's unguarded special train from Washington pulled up at Warrenton Junction, where there was only one Union official, Mosby's men had just crossed the track in pursuit of some Federal cavalry.
But neither these two Confederate thorns in the side nor the more serious Federal failures could stop the general advance. Nor yet could Butler's lack of success on the James. Butler had seized and fortified. an exceedingly strong defensive position at Bermuda Hundred on a peninsula, with navigable water on both flanks and in rear, and a very narrow neck of land in front. The only trouble was that it was as hard for him to surmount the Confederate front across the same narrow neck as it was for the enemy to surmount his own. He was, in fact, bottled up, with the cork in the enemy's hands. He did send out cavalry from Suffolk to cut the rails south of Petersburg. But no permanent damage was done there. Petersburg itself, which at that time was almost defenseless, was-not . taken. And in the middle of the month Beauregard attacked Butler so vigorously as to make the Army of the James rather a passive than an active force till it was presently, absorbed by Grant when he arrived before Richmond in June.
Grant felt perfect confidence only in four prime elements of victory: first, in his ability to wear Lee down by sheer attrition if other means failed; next, in his own magnificent army; then in Sherman's; and lastly in Sheridan's cavalry. His supply and transport services were nearly perfect, even in his own most critical eyes. "There never was a corps better organized than was the quartermaster's corps with the Army of the Potomac in 1864." His field engineering and his signal service were also exceedingly good. At every halt the army threw up earth and timber entrenchments with wonderful rapidity and skill. At the same time the telegraph and signal corps was busy laying insulated wires by means of reels on muleback. Parallel lines would be led to the rear of each brigade till quite clear, when their ends would be joined by a wire at right angles, from which headquarters could communicate with every unit at the front.