Several North Carolina brigades commanded by Brig. Gen. Robert Ransom moved south to link up with the left flank of the 26th South Carolina and Virginians from Brig. Gen. Henry Wise’s brigade to repair the line and support McMaster. A number of disorganized Union thrusts were repulsed. By 8:30 am, after Potter’s and Willcox’s divisions entered the fray, a large part of the Union IX Corps, about 10,000 men, had reached the destroyed enemy salient, most of them milling around the Crater. When Willcox led his division into action, he ordered a brigade commanded by Brig. Gen. John Hartranft to expand the breakthrough south of the Crater. Its lead regiments, however, were once again drawn inexorably toward the massive hole, where they became entangled with Ledlie’s troops. Two other regiments simply halted on the rising slope. Stunned by this development, Willcox strongly cautioned Burnside against advancing any more troops.
Meade, exploding in anger when informed of the bottleneck at the Crater, summarily ordered Burnside to have all Union troops push forward to the crest of Cemetery Hill, regardless of their current dispositions. Willcox tried hard to comply, ordering the 27th Michigan straight into the teeth of Wise’s Virginians, who halted the advance in minutes. Meanwhile, Willcox’s second brigade, under Colonel William Humphrey, moved up, only to find its front partially blocked by Hartranft’s stalled column. Under fire and eager to advance, Humphrey sent his entire command surging across the abatis-strewn field, where they crashed into the Confederate works, capturing prisoners and relieving, for a while, the pressure on the south flank of the Crater. Humphrey’s success was fleeting, however; the Virginians rallied, and South Carolinians firing at the Crater turned their attention to the new threat. Humphrey’s left flank quickly crumbled and three Michigan regiments found themselves isolated within the Confederate lines, taking fire from three directions.
Burnside’s ambitious plan to seize Petersburg and bring a quick end to the war was disintegrating in a jumble of Union command failures and unexpectedly stiff Confederate resistance. Meade continued to insist that all Union units rise up en masse and take Cemetery Hill. Burnside opted to take the word of his commanders on the scene, who informed him that there was literally no more room for added units to deploy and that any reinforcements would be a waste of manpower. Nevertheless, sometime after 7 am, Meade ordered Burnside to commit his fourth and last division, Ferrero’s USCT troops. As his units advanced into the teeth of enemy fire, Ferrero clambered into Ledlie’s bomb shelter, where he huddled, sharing a bottle of rum with Ledlie, for the remainder of the battle.
The USCT advance was blocked by a steady flow of returning wounded, panicked comrades, and Confederate prisoners coming from the front. After Lt. Col. Joshua Sigfried ordered his brigade forward, the black troops stolidly negotiated the obstacles leading to the front only to come under galling fire all along their column. Parts of the two leading regiments forced their way through the congested mass inside the Crater. while others skirted the abyss north of it, all disappearing into the honeycomb of enemy trenches and bombproofs. In the turmoil, the 30th USCT fired on the 9th New Hampshire and rendered it hors de combat. Despite the blunder, the black troops moved into the Rebel entrenchments and confronted the 17th South Carolina, inflicting and suffering heavy casualties as they pressed ahead.
More of Sigfried’s brigade followed and helped launch the fiercest Union attack of the day as the African American fighters captured the damaged cavalier trench held by Elliot’s survivors, all the while screaming, “No quarter, remember Fort Pillow!” in reference to the recent notorious slaying of several dozen black troops during or after the battle for the West Tennessee fortification. They rounded up hundreds of prisoners, killing any who showed the slightest resistance, and after hours of stalemate it seemed that the breach might begin to expand.
Ferrero’s second brigade commander, Colonel Henry Thomas, however, trying to follow up on the success of Sigfried’s men, lost control of his regiments when they descended into the maze north of the Crater or moved into the pit itself. Thomas managed to get some of his men formed on Sigfried’s left flank west of the cavalier trench, but a barrage of shells and bullets blasted them back into the trench. McMaster’s Confederates, still sheltering inside the creek depression 200 yards to the west, massed their fire into the van of Sigfried’s advance, wrecking it. Ferrero’s depleted ranks fell back into the cavalier trench.
Burnside, who would be instructed by Meade to order a withdrawal in less than an hour, still believed his men had another charge in them. He ordered Sigfried and Thomas to again attack Cemetery Hill, reinforced by Marsh and Bartlett, Ledlie’s two brigade commanders. Waving a regimental flag, Bross of the 29th USCT climbed out of the cavalier trench and exhorted his men to follow him. The courageous remnants of the division moved up and formed a ragged line on the colors. With Cemetery Hill 500 yards away in plain sight, the USCT troops once again moved forward into the fiery summer morning.
Shortly after arriving at the front, Mahone saw the confusion in the Federal ranks but, concerned about the enemy’s numbers, he called for his third brigade—Willcox’s Alabama troops under the command of Colonel John Sanders—to come up as well. Colonel David Weisiger’s five Virginia regiments had led Mahone’s initial march, moving through the covered way into the creek depression where McMasters’ South Carolinians had made their heroic stand. Mahone sent the Georgians to support Weisiger’s right flank, and as the Rebels moved into place, word spread that black units had taken part in the last attacks and that no quarter had been asked or given. By 9 am Mahone’s units were in place, locked and loaded, with bayonets fixed.
About 200 black troops had answered Bross’s call and begun advancing west from the cavalier trench, their cheers catching the attention of Weisiger’s men. In a line 200 yards wide and three lines deep, Weisiger’s Virginians, backed by two North Carolina regiments, McMaster’s survivors, and parts of two Georgia regiments, leaped out of the creek depression and charged the isolated and outnumbered USCT column, which floundered and fell back. Mahone’s gray wave approached the cavalier trench, where it was met with a sweeping Union volley. The fire tore gaps in the Confederate line but couldn’t slow it down, the attackers sweeping over the last few yards and crashing into the trench.
Fierce fighting exploded along the entire front, bayonets flashing and gun butts flailing. With the cavalier trench cleared, the Confederate defenders worked their way toward the crowded blue maze north of the Crater, killing with abandon and taking few prisoners, white or black. Again panic struck the Union ranks, and mobs of men turned and headed back for the Crater only to find the intervening ground a cauldron of lethal crossfire. With Mahone’s attackers in hot pursuit, most of the fleeing bluecoats tumbled into the perceived safety of the Crater. There, in a ghastly turn of events, some panicky Union troops bayoneted incoming black troops, fearing enemy reprisals if they were captured fighting alongside the black troops.
Approaching Confederates deployed movable Coehorn mortars 50 feet from the Crater and began sending a steady stream of shells into the churning morass. “We got closer and closer to the enemy,” recalled a Confederate battery commander, “until we were throwing shells with such light charges of powder that they would rise so slowly as to look as if they could not get to the enemy, who were so close that we could hear them cry out when the shells would fall among them, and repeatedly they would dash out and beg to surrender.” Mahone, whose Virginians by now had captured most of the line north of the Crater, ordered a line of sharpshooters to target the western edge of the Crater while sending the rest of his Georgia brigade against its southern flank. The Georgians made two bloody attacks and extended Weisiger’s line to the south but failed to take the trenches south of the Crater. The Union mass in the smoldering rubble stubbornly held on, resisting all efforts to push them out of their man-made hole.
Mahone’s attack had taken about an hour. Before it began, Burnside had begged Meade to allow fresh V Corps units to join the fray, but at 9:30 am Meade sent orders instead for Burnside to begin conducting a withdrawal. The angry Burnside sought out Meade and in “language extremely insubordinate” demanded the operation continue with the aid of V Corps. After Grant arrived and backed Meade, a disconsolate Burnside returned to his headquarters and prepared to pull his commands back to safety. He would, however, be in no particular hurry to do so. Scores of additional Union troops would die because of his tardiness.
As the merciless summer sun baked the horrid pit, Union soldiers used the bloated bodies of dead comrades as makeshift parapets. Some Federals braved the hell of no-man’s-land in a heroic effort to bring water and ammunition back to their comrades. Despite the dreadful conditions and abject confusion, the Federals continued somehow to keep the defenders at bay, throwing back a series of limited Confederate thrusts. More and more survivors crawled out of the Crater and headed back toward their own lines, enduring a galling crossfire that killed and wounded hundreds more. In the pit’s southern recesses, Chippewa Indian riflemen from the 1st Michigan Sharpshooters covered their heads and sang their death songs amid the deafening roar of battle. At 12:30 pm, word arrived that Burnside had given up and ordered a withdrawal; Union officers at the front were told to use their discretion as to the timing and method of withdrawal.