The Battle of Gettysburg, fought on the first three days of July in 1863, resulted in more than 51,000 total casualties (dead, wounded, missing, captured), including more than 7,000 dead, yet it began by accident on the morning of July 1, 1863. Neither side planned to fight at Gettysburg, but as both armies approached south-central Pennsylvania, the road networks drew them toward that town of about 2,400 residents. Once the fighting started, more than 160,000 soldiers occupied the town and its surroundings.

In late June 1863, General Robert E. Lee’s Army of Northern Virginia was engaged in its second invasion of the north, hoping to fight a defensive battle on ground of its own choosing that would force the Union to make peace. The Union Army of the Potomac, having been defeated by Lee’s army at Fredericksburg in December 1862 and Chancellorsville in May 1863, switched commanders, with General George Meade replacing General Joseph Hooker.

Meade’s army was searching for the Army of the Potomac with the intention of fighting in northern Maryland along a stream called Pipe Creek. Meade, from his headquarters in Taneytown, Maryland, issued the Pipe Creek Circular on June 30, 1863, which planned for a defensive battle along a line “with the left resting in the neighborhood of Middleburg, and the right at Manchester, the general direction being that of Pipe Creek.” Meade ordered General John Reynolds to withdraw from Gettysburg and redeploy at Middleburg.

Union cavalry led by General John Buford entered Gettysburg on June 30, establishing temporary headquarters at the Eagle Hotel and later at the Lutheran Seminary located on Seminary Ridge. Buford’s scouts spotted Confederate infantry marching towards Gettysburg in large numbers.

On June 30, Buford decided to hold at Gettysburg until Reynolds’s infantry arrived. But before Reynolds could get there, Confederate troops led by General Henry Heth’s two brigade commanders, James Archer and Joseph Davis, moved toward the town along the Chambersburg Pike. At around 7:30 am, one of Buford’s forward-posted vedettes (Marcellus E. Jones from Illinois) fired the first shot that began the Battle of Gettysburg.

General Lee had ordered Heth not to bring on a general battle, but believing he was dealing with a small militia force, Heth decided to fight it out. He soon learned that he was engaged with Federal cavalry, but continued moving forward under the belief that his infantry regiments could easily defeat dismounted cavalry. But Buford’s men were stubborn that morning. So Heth kept pouring in more infantry, and Buford’s men fell back from Herr Ridge to McPherson’s Ridge.

Before the Southerners could rout Buford’s cavalry, Reynolds’s infantry arrived in force, led by the Iron Brigade, and stormed into a wooded area near Willoughby Run. The fighting was intense on both sides of the Chambersburg Pike. Reynolds was killed by a Confederate sharpshooter. The Confederates’ superior numbers pushed the Union infantry back to Seminary Ridge.

Meanwhile, Southern troops arrived from the north, forcing Union forces through the town toward Cemetery Hill, Culp’s Hill, and Cemetery Ridge — the high ground east and south of the town. General Lee ordered General Richard Ewell to take Cemetery Hill “if practicable,” but Ewell decided it was not practicable, and Union forces held the high ground on the evening of July 1.

Historian Noah Andre Trudeau, whose Gettysburg: A Testing of Courage is one of the best one-volume studies of the battle, writes that the fighting on July 1 was a “battle of brigades and regiments, not of divisions and armies.” “Nowhere was it written in stone,” he continues, “that the two sides would fight at Gettysburg, nor was the slow escalation inevitable once the combat began.”

With Lee’s invasion of the North, a battle was undoubtedly destined to occur, but it was road networks, topography, and the individual decisions of Union and Confederate commanders that transformed the small town of Gettysburg into a large universe of battle.

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