Who Won The First Day?
The Confederacy won the first day's battle, though the leadership of the Army of Northern Virginia had been somewhat wanting. Lee made a number of serious errors by insisting on holding a division back in reserve throughout the fighting, when it might have turned a Union reverse into a disaster, and more importantly, had not directed the battle. Instead, he suggested when he ought to have commanded. This was most notable late in the afternoon, when he gave Ewell the option of taking Cemetery Hill before dark,certainly one of the most unusual orders an army commander ever gave to one of his corps commanders. Lee also failed to coordinate the actions of his units, so that each division commander pretty much fought independently. Such coordination as did occur was largely fortuitous, as a result of individual commanders seizing the initiative.
Lee's subordinates had not done well either. To be sure, A.P. Hill had performed excellently against McPherson's Ridge in the afternoon, effectively coordinating the actions of two divisions. But Heth had completely bungled the opening action with Buford's cavalry, and gone on to do likewise in his initial efforts against the 1st corps on McPherson's Ridge. Rodes and his brigade commanders had badly mishandled their attack on the 1st corps, and Early had been slow in getting his division into action. Stuart's absence severely hampered a more skillful conduct of the battle, for the Confederate generals had to operate without information which only his cavalry could have provided.
Great tenacity and courage had been demonstrated, but little tactical finesse, resulting in too many frontal assaults when flank attacks would have served. Had the action been better handled, the Union would have suffered a far greater defeat at far less cost.

Although seriously defeated, the Union forces had done fairly well, but they could have done better. There was no question that the troops were skilled and determined, but some of their leaders were wanting. Buford's decision to dismount his troopers and fight north and west of Gettysburg was a good one, as was Reynolds' decision to support him. But it is doubtful that Reynolds intended to undertake anything but a delaying action, rather than seek a grand battle on two fronts, north and west of Gettysburg. For this Doubleday and Howard bear responsibility, particularly the latter, who put the 11th corps into the broad valley north of the town. Howard's selection of Cemetery Hill as a reserve position was noteworthy, however. Hancock arrived on the field too late to influence the course of the action. However, once there, he had done very well, by not taking counsel in fears, rapidly putting together a viable defense on Cemetery Ridge and Culp's Hill so soon after a serious reverse and by urging that a stand be made in the new position. On the other hand, Slocum performed poorly because he failed to march to the sound of gunfire which his men heard shortly after noon while eating lunch at Two Taverns. Not six miles from the battle, he had missed an opportunity to turn the action into a draw. Lower level leadership, however, seems to have been skillful, despite the movements which split the front of the 1st corps. Had Union forces been better led, they might have inflicted a modest defeat on the advancing Confederates. They could, of course, have been worse handled, and an even greater reverse might have resulted.