On the same day the enemy released "his hold on the Susquehanna." Informed, on the 28th, of Hooker's intended descent on the line of his retreat, Lee suddenly changed his order of march upon Harrisburg to a retrograde by securing a footing east of the South Mountain range, he hoped to keep open his imperilled communications. Ewell was then in occupancy of Carlisle and York; Longstreet and Hill were at or near Chambersburg. The three corps were directed to concentrate at Gettysburg; and on the 29th were en route to that important point.
Buford, reaching Gettysburg on the evening of the 30th, pushed out reconnoissances on the roads leading north and west. He then ascertained that the Confederates were marching toward that point, their columns having already reached Cashtown, on the Chambersburg road, and Heildersburg, on the Carlisle road. Of this Meade was at once informed. His advance, at that moment, had reached Taneytown and vicinity, though General Reynolds, with the First and Eleventh corps, had approached within four miles of Gettysburg, with orders to occupy the town on the following morning. Meade's want of correct knowledge, both of the topography of the country and of the enemy's designs, led him to locate a temporary line, stretching from Middleburg to Manchester (Pipe Creek), considering it a good one for general battle, should it be Lee's design to advance upon him. Behind this line he ordered the trains, and the several corps were directed to be put in the lightest possible condition. The Federal disposition on the night of the 30th was: headquarters at Taneytown; Third Corps at Summitsburg; Second, at Taneytown; Fifth, at Hanover; Sixth, at Manchester; Twelfth, at Two Taverns; First and Eleventh, advanced upon Gettysburg, at Marsh Run. Kilpatrick's cavalry were observing on the east beyond Hanover junction.
On the morning of July 1st the advance of Hill's corps struck Buford's lines at Willoughby Run, a mile or more northwest of Gettysburg. A sharp skirmishing fight at once followed, Buford resolving to hold the enemy there until the infantry should come up. Reynolds, hearing the sounds of battle, hurried forward the First division (Wadsworth's) of the First Corps, with orders for the other divisions of First and Eleventh corps to follow. The advancing division reached the point of conflict at 10 A.M. It was found that the enemy were still beyond the second of the two ridges lying west of Gettysburg; the first, or Seminary Ridge, being one-half mile, and the second one mile and a half, distant from the town. At the base of the second flowed Willoughby Run, along whose banks, and on the western declivity, Heth's division, of Hill's corps, was formed. Reynolds appears to have resolved upon delaying the Confederate advance at that point. As the Federal army lay from seven to thirty-two miles away, it was absolutely imperative, if the heights of Gettysburg were retained, that the Confederates should be held where they were for a day.
Wadsworth's two brigades were quickly disposed for action. Cutler's five regiments were on the right and left of the Chambersburg turnpike, as well as using for cover the embankment and "cuts" of a then unfinished railway running parallel with and close to the highway. Hall's Maine battery was placed between these roads, sustained by three regiments under Wadsworth's direct command, which constituted the extreme Federal right; while Reynolds in person directed the disposition of the other two regiments to the left of the road. The second brigade Meredith's "Iron Brigade" - under General Doubleday's direction, was assigned to the Federal left, covering the road from Millerstown, and occupying a strip of woods into which the enemy already had penetrated.
The enemy opened fire sharply on the forming lines, and while directing the disposition on the right General Reynolds was killed. Davis's Mississippians, advancing over the run, turned Wadsworth's three regiments, which, after a severe fight, were withdrawn by way of the turnpike, to re-form under the lee of Seminary Ridge. This retirement left the battery unsupported, and it was retired after severe loss. The two regiments under Cutler were thus exposed to a flank assault. Seeing this, Doubleday ordered in his reserve regiment (Sixth Wisconsin), and the three regiments, facing about, charged upon the Mississippians, then forming along the railway for a charge. This movement, executed with celerity and intrepidity, was so much of a surprise to the enemy that, after a short conflict, nearly two entire regiments, with their colors, were captured.
“Jesus replied: "Love the Lord your God with all your heart and with all your soul and with all your mind." This is the first and greatest commandment. And the second is like it: "Love your neighbor as yourself."”
– Matthew 22:37-39