By nightfall of the first, both armies were in state of readiness for the conflict. The Union army was on the defensive. It was sufficient that it should hold its ground and repel all assault. The Confederates must advance and carry the Federal position in order to succeed. How this should be done was not agreed on by the Confederate commanders. General Lee formed a plan of direct assault; but General Longstreet was of opinion that a movement of the army to the Union left flank would be preferable, and that by that method the flank might be turned and the position of Meade carried with less loss and much less hazard.
Longstreet, however, did not oppose the views of his commander to the extent of thwarting his purpose or weakening the plan adopted. On the second of July the battle began in earnest about noon. The Confederates advanced against the Union centre and left, and at a later hour a strenuous and partly successful attack was made on the Federal right. But complete success was not attained by Lee in any part of the field. About sundown the Confederates gained considerable advantage against Slocum, who held the line along Wolf Hill and Rock Creek; and on the Union left a terrible struggle occurred for the possession of Great and Little Round Top. In this part of the field the fighting continued until six o'clock in the evening; but the critical positions still remained in the hands of the Federals.
In the centre the contest was waged for the mastery of Cemetery Hill, which was the key to the Union position. Here were planted batteries with an aggregate of eighty guns, and here, though the assaults of the Confederates were desperate and long continued, the integrity of the Federal line was preserved till nightfall. The fighting along a front of nearly five miles in extent continued in a desultory manner until about ten o'clock on the July night, when the firing for the most part ceased, leaving the two armies in virtually the same position which they had occupied the day before.
This signified, however, that thus far the advantage was on the Union side; for on that side the battle was defensive. The Confederate army had come to a wall, and must break through or suffer defeat. The burden of attack rested on the Confederate side; but General Lee did not flinch from the necessity. In the darkness of night both he and the Union commanders made strenuous preparations for the renewal of the struggle on the morrow.
On the morning of the third both armies seemed loath to begin the conflict. This phenomenon is nearly always witnessed in the case of really critical battles. It was so at Waterloo, and so at Gettysburg. It seems that in such crises the commanders, well aware of what is to come, wait awhile, as though each would permit the other to strike first. As a matter of fact, the topmost crest of the Civil War had now been reached; and from this hour the one cause or the other must decline to the end.
The whole forenoon of the third of July was spent in preparations. There was but little fighting, and that little was desultory. At midday there seemed to be a lull along the whole line. Just afterward, however, General Lee opened from Seminary Ridge with about one hundred guns, directing his fire against the Union centre on Cemetery Hill. There the counter position was occupied by the American artillery of about equal strength, under command of General Hunt. The cannonade burst out at one o'clock with terrific roar. Nothing like it had ever before been seen or heard in the New World. Nothing like it, we believe, had ever up to that time been witnessed in Europe. Certainly there was no such cannonade at Waterloo. For about an hour and a half this tremendous vomit of shot and shell continued. It was the hope of General Lee to pound the Union batteries to pieces, and then, while horror and death were still supreme in the Union centre, to thrust forward an overwhelming mass of his best infantry into the gap, cut Meade's army in two, plant the Confederate banner on the crest of the Union battle line, and virtually then and there achieve the independence of the Confederate States.
It seems that an action of General Hunt, about half-past two, flattered Lee with the belief that he had succeeded. Hunt adopted the plan of drawing back his batteries over the crest of the hill, for the double purpose of cooling his guns that were becoming overheated and of saving his supply of ammunition, that was running low. The Union fire accordingly slackened and almost ceased for a while. Nor was Lee able to discover from his position but what his batteries under General Alexander had prevailed. It looked for the moment as though the battle were lost to Meade, and that victory was in the clutch of his antagonist.
Already a Confederate charge of infantry had been prepared. About 18,000 men, in three divisions, under Armistead, Garnett and Pettigrew, and led by General George E. Pickett, of Virginia, had been got into readiness for the crisis which had now arrived. Longstreet was the corps commander, and through him the order for the charge should be given. General Lee had himself made the order, but Longstreet seeing, as he believed the inevitable, hesitated and turned aside. It was not a refusal to send an army to destruction, but the natural hesitation of a really great commander to do what he believed was fatal to the Confederate cause. Pickett, however, gave his salutation to Longstreet, and presently said: "Sir, I am going to move forward!"
Then began the most memorable charge ever witnessed in America. The Confederate column was three-fourths of a mile in length. It was directed against the Union centre, where it was supposed the Confederate fire had done its work. What ensued was the finest military spectacle that had been seen in the world since the charge of the Old Guard at Waterloo; and the results were alike! The brave men who made the onset were mowed down as they crossed rapidly the intervening space. Hunt's batteries were quickly run back to their position, and began to discharge their deadly contents against the head of the oncoming column. That column veered somewhat to the right as it came. The line staggered, but pressed on. It came within the range of the Union musketry. Gaps opened here and there. Armistead, who led the advance, saw his forces sink to the earth; but he did not waver. Nearer and nearer the column came to the Union line. It struck the Union line. There was a momentary melee among the guns, and then all was over. Hancock's infantry rose with flash on flash from among the rocks by which they were partially protected. The Confederates were scattered in broken groups. Retreat was well-nigh impossible. The impact of the charge was utterly broken, and the Confederate line was blown into rout and ruin. Victory hovered over the National army. The Confederate forces staggered away under the blow of defeat. Night came down on a broken and virtually hopeless cause. The field was covered with the dead and dying. Two thousand eight hundred and thirty-four Union soldiers had been killed outright; 13,709 were wounded, and 6643 were missing, making a total of 23,186 men. The Confederate loss was never definitely ascertained, but was greatly in excess of that of the Federals. The best estimate has been fixed at 31,621. The grand total of losses in those fatal three days thus reached the enormous aggregate of 54,807!