How Brig. Gen. Daniel Sickles singlehandedly shifted the position of the entire union army, resulting in horrific casualties on both sides.
By the morning of July 2, most of the infantry units of both armies had arrived on the field. The Union army’s defensive position had assumed the shape of a fish hook, beginning on Culp’s Hill, curving around Cemetery Hill and proceeding down Cemetery Ridge. Maj. Gen. Daniel Sickles, however, dissatisfied with the position of his III Corps on southern Cemetery Ridge had advanced west, without orders, onto higher ground in the area of the Peach Orchard, the Wheatfield and Devil’s Den.
Lee’s plan called for coordinated attacks on both Union flanks. While two divisions demonstrated against the Union right at Culp’s and Cemetery Hills, Lt. Gen. James Longstreet’s First Corps would move to the south and make the main attack on Union left. Due to faulty intelligence, exacerbated by the absence of Maj. Gen. J.E.B. Stuart’s cavalry, the Confederate high command was not aware of Sickles’s redeployment. A series of delays kept the Confederate attacks from beginning until after 4:00 p.m.
Reports of Confederate movements were relayed to the Union command by a detachment of signalmen on the rocky heights of Little Round Top. Realizing the strategic significance of this nearly undefended hill, the army’s chief engineer, Maj. Gen. Gouverneur Warren, sprang into action with a desperate plea for any available troops. Luckily, Commanding general George Meade had sent Maj. Gen. George Sykes’s V Corps to reinforce the Union left flank and Col. Strong Vincent redirected his brigade to take up position on Little Round Top — without waiting for orders from his direct superiors.
Longstreet’s lead division under Maj. Gen. John Bell Hood advanced and encountered stubborn resistance from Union infantry holding a strong defensive position around the craggy rock formation known as Devil’s Den, even as elements of the force skirted this action and moved toward the Round Tops. Col. Vincent had just arrived on Little Round Top when Texans and Alabamians assaulted the rocky height. The resulting fight is one of the war’s most celebrated engagements, concluding in dramatic fashion when the regiment on the far left of the entire Union line, the 20th Maine, having expended its supply of ammunition, executed a precise and unexpected bayonet charge, sweeping the hillside clear of its equally exhausted foes.
In the bloodiest fighting at Gettysburg, the combat spread to the Wheatfield, the Peach Orchard and as far north as Cemetery Ridge, where a near-suicidal bayonet charge by the 1st Minnesota, bought time for reinforcements to arrive and push back some of the last of Lt. Gen. A.P. Hill’s Confederates. Of the 262 men who made the charge, only 47 escaped unscathed — a staggering 82 percent casualty rate. While the Southerners captured Devil’s Den and the Peach Orchard, the Federal line on Little Round Top and Cemetery Ridge held firm.
On the Union right, the earlier Confederate demonstrations had escalated into full-scale assaults on Culp’s Hill and East Cemetery Hill by about 7:00 p.m. Although Culp’s Hill, in particular, had seen many of its original defenders sent to face the attacks elsewhere on the line, the remaining troops had constructed a substantial network of earthworks and repulsed these attacks. Here, as elsewhere on the second day, the Confederates gained ground, but were unable to dislodge the Union defenders.