Battle of Gettysburg

Background

In May 1863 Robert E. Lee's Army of Northern Virginia beat Joseph Hooker's Army of the Potomac at Chancellorsville, but lost Stonewall Jackson, mortally wounded by his own men. Lee reorganised his infantry into three corps under James Longstreet, Richard Ewell and A. P. Hill, and in June marched north through the Shenandoah and Cumberland valleys into Pennsylvania. He wanted to take the war out of exhausted Virginia, feed his army from Northern farms, draw the Union army away from the Rappahannock and, if he could, win a victory on Northern soil that would weaken the North's will to go on. In the west, meanwhile, Grant was besieging Vicksburg.

Lee's cavalry chief, J. E. B. Stuart, given loose orders, rode round the eastern side of the Union army with three of his best brigades and lost touch with Lee for the crucial days. Lee learned only on 28 June, from a spy, that the Union army had crossed the Potomac and was close behind him. That same day Lincoln replaced Hooker with Major General George G. Meade, a Pennsylvanian who had commanded V Corps. Lee ordered his scattered corps to concentrate east of the South Mountain around Cashtown and Gettysburg.

Gettysburg, a county town of a few thousand people, mattered because roads from every direction met there. On 30 June John Buford's Union cavalry division occupied it and posted pickets on the ridges to the west and north. On the morning of 1 July Henry Heth's division of Hill's corps marched east down the Chambersburg Pike towards the town. Neither army commander had chosen to fight there.

The armies

Meade's Army of the Potomac had seven infantry corps (I, II, III, V, VI, XI and XII) and a cavalry corps: about 94,000 men by the American Battlefield Trust's count, with estimates from 88,000 to over 104,000, and some 360 guns. Meade had been in command for three days. His best subordinates included John Reynolds of I Corps and Winfield Scott Hancock of II Corps; Daniel Sickles of III Corps was a political general with no formal military training. The army's artillery, under Henry Hunt, was well organised, with a large reserve of rifled guns and smoothbore Napoleons. The infantry carried rifled muskets, the cavalry mostly single-shot breech-loading carbines.

Lee's army numbered about 72,000 (65,000–75,000 in most estimates) with some 270 guns, in three infantry corps of three divisions each and Stuart's cavalry division. It was a veteran army, confident after Fredericksburg and Chancellorsville, but two of its three corps commanders, Ewell and Hill, were new to corps command, and Lee's habit of giving discretionary orders had worked best with Jackson. Confederate artillery was handicapped by unreliable fuses and fewer rifled guns.

Geography shaped the fighting. Once the Union army settled on its fishhook of hills south of the town, Meade held the shorter, inner line and could shift reserves across it quickly, while Lee's corps had to work round a much longer outer arc.

The battle

CDB90 treats the three days as a single engagement, number 199 (GETTYSBURG), from 10:00 on 1 July to 15:00 on 3 July. Times below are approximate; sources differ by up to an hour.

1 July: west and north of the town. At about 07:30 Heth's leading brigades met Buford's dismounted cavalry west of Gettysburg, and by mid-morning had pushed them back to McPherson Ridge. Reynolds's I Corps arrived around 10:00–10:30; Reynolds was killed almost at once, but the Iron Brigade broke Archer's brigade, capturing Archer, and Union infantry trapped part of Davis's brigade in the unfinished railroad cut. After a midday lull, Ewell's corps came down from the north. Robert Rodes's division attacked from Oak Hill around 14:00, and Jubal Early's division, arriving on the Harrisburg Road, struck the exposed right of Oliver Howard's XI Corps at Barlow's Knoll. XI Corps gave way, I Corps was driven off Seminary Ridge, and by late afternoon the survivors were streaming through the town to Cemetery Hill, losing thousands as prisoners. Hancock, sent by Meade, helped Howard rally them there. Lee told Ewell to take Cemetery Hill "if practicable"; Ewell judged it was not, and the Union army spent the night digging in on Cemetery Hill and Culp's Hill.

2 July: the Union left. By morning Meade's line ran in a fishhook from Culp's Hill round Cemetery Hill and south along Cemetery Ridge towards the Round Tops. Lee ordered Longstreet to attack the Union left, but the approach march to avoid observation took most of the day. Meanwhile Sickles moved III Corps forward, without orders, to higher ground along the Emmitsburg Road around the Peach Orchard. Hood's division attacked just after 16:00 at Devil's Den and towards Little Round Top, which Meade's chief engineer, Gouverneur Warren, had found nearly unoccupied; Strong Vincent's brigade reached it just in time, and the 20th Maine held its southern end with a bayonet charge. McLaws's division attacked the Wheatfield and the Peach Orchard from about 17:00, and the fighting in the Wheatfield swung back and forth as Meade fed in brigades from V, II and VI Corps. Sickles lost a leg and III Corps was wrecked. Anderson's division of Hill's corps pressed on against Cemetery Ridge, where Ambrose Wright's brigade briefly reached the crest and Hancock threw the 1st Minnesota into a desperate counter-attack to buy time. At dusk Ewell attacked East Cemetery Hill, which held, and Culp's Hill, where Edward Johnson's division took empty Union entrenchments on its lower slopes.

3 July: Culp's Hill, the bombardment and Pickett's Charge. From before dawn until about 11:00 the Union XII Corps fought to retake its works on Culp's Hill and did so. Lee decided to attack the Union centre on Cemetery Ridge. At about 13:00 some 150–170 Confederate guns opened the largest bombardment of the war; much of it overshot, and Union artillery slowed its fire to save ammunition. At about 15:00 roughly 12,500 men (estimates run from 10,500 to 15,000) under Pickett, Pettigrew and Trimble advanced across nearly a mile of open ground, aiming for a clump of trees on the ridge. Artillery and Hancock's II Corps cut them down; Armistead led a few hundred men over the stone wall at the Angle and fell mortally wounded, and the survivors fell back. Hancock was badly wounded. East of the town, Stuart's cavalry, which had reached Lee only on 2 July, was checked by David Gregg's and George Custer's brigades on East Cavalry Field, and to the south Elon Farnsworth was killed in a hopeless mounted charge ordered by Judson Kilpatrick.

Aftermath

The two armies lost between them about 46,000–51,000 men killed, wounded, captured or missing: some 23,000 Union and 23,000–28,000 Confederate, a third or more of Lee's army. Between 7,000 and 8,000 were killed outright: the Union returns count 3,155 dead, and Confederate counts run from 3,903 to 4,708. The town was left with thousands of wounded and unburied dead.

Lee waited on 4 July for an attack that did not come, then began his retreat that evening in heavy rain, with a wagon train of wounded some 17 miles long. The flooded Potomac trapped him at Williamsport until he crossed on the night of 13–14 July. Lincoln, who had hoped Meade would destroy Lee's army, was bitterly disappointed. Vicksburg surrendered to Grant on 4 July, and the two victories together are usually treated as the war's turning point, though some historians argue Gettysburg changed less than its fame suggests. On 19 November Lincoln dedicated the Soldiers' National Cemetery with the Gettysburg Address.

The arguments began almost at once. Lost Cause writers after the war blamed Longstreet, by then a Republican and a critic of Lee, for slowness on 2 July and for Pickett's Charge; modern historians spread the responsibility more widely, to Lee's own plans and orders, Stuart's absence, and Ewell's caution on 1 July. The copse of trees that the battlefield's first historian, John Bachelder, promoted as the "High Water Mark" became the focus of the memorial landscape, marked by a monument in 1892.

Wargaming it

Gettysburg is the most-gamed battle of the American Civil War, and it rewards splitting into its three days. The whole battle works at brigade level, with one base or unit per brigade and turns of 30 minutes to an hour, on a table about four miles by four. Each day also stands alone: the meeting engagement of 1 July, Longstreet's attack and the Wheatfield on 2 July, or Culp's Hill and Pickett's Charge on 3 July. At regimental level, Little Round Top, Devil's Den, the railroad cut and East Cavalry Field make tight smaller games.

The key terrain is the fishhook itself: Culp's Hill and Cemetery Hill, the low line of Cemetery Ridge, the Round Tops, and the stone walls, woods and boulders that broke up attacks. Rules should give the defender the benefit of interior lines and make co-ordinating a large attack across a long outer arc genuinely hard.

The first day is a race of arrivals, and scenario designers have to decide whether corps enter on a fixed or variable schedule. The what-ifs are many: Ewell attacking Cemetery Hill on the evening of 1 July, Longstreet attacking on 2 July in the morning or moving round the Union left as he later said he urged, Sickles staying on Cemetery Ridge, Little Round Top left unoccupied, or Stuart present from the start. Balance is the usual trap: historically the Confederates lose on 3 July, so victory conditions should reward them for taking ground or inflicting losses by a deadline.

Maps and pictures