On the night of June 12, 1864, the Army of the Potomac rose from its trenches at Cold Harbor and vanished. All 115,000 men—infantry, cavalry, artillery, engineers, and a supply train stretching back fifty miles—walked south into the darkness. Cooking fires were left burning, knapsacks propped against logs, so that the empty camp would look occupied. Regimental bands played “Yankee Doodle” at intervals along the line, not in celebration but to mask the creak of wagon wheels and the clatter of canteens.
Ahead of them lay swamps that swallowed men to the knee and, at the end of the road, the James River, two thousand feet wide. Ulysses S. Grant later called the move “a hazardous one. ” He was threading an entire army through the dark in enemy territory, and Robert E.
Lee, thirty-five miles away, had no idea any of it was happening. By June 1864, Grant was running out of options. He was forty-two years old, a tanner’s son from Ohio who had failed at farming and business before the war rescued him from obscurity. For six weeks he had been bleeding men at a horrifying rate.
Cold Harbor still carried the stench of that failure. On June 3, Grant ordered a frontal assault against Lee’s entrenched lines. In less than thirty minutes, seven thousand Union soldiers fell. Some pinned their names to their coats before the charge, certain they would not survive to be identified.
Grant later wrote, “I have always regretted that the last assault at Cold Harbor was ever made. ” He would not make that mistake again. Lee, fifty-seven years old and married to the great-granddaughter of George Washington, had been beating Union commanders for three years. But his body was failing—heart disease, chronic back pain, and bouts of dysentery left him gray-faced and exhausted.
He sometimes commanded from a camp chair when he could not mount his horse. His army of roughly sixty thousand was dug into some of the strongest field works ever constructed, but his men were hungry. Rations had been cut to half the Union standard, and many were now conscripts swept up by the Conscription Act of 1862. Grant faced a brutal calculation.
He could not break Lee’s lines by frontal assault. He could not outflank Lee to the north because of the Chickahominy Swamps. He could not simply wait, because Lincoln faced re-election in November, and if the war looked stalled, the Peace Democrats might win and negotiate Confederate independence. Grant needed a move so bold that Lee would not believe it even as it happened.
His plan was to disengage from Cold Harbor after dark, march south across the Chickahominy, cross the James, and link with Benjamin Butler’s Army of the James at Bermuda Hundred—then strike Petersburg before Lee understood what had happened. Simple to describe, monstrous to execute. If Lee detected the withdrawal and attacked while the army was strung out over fifty miles of swamp road, the result would be destruction of the Army of the Potomac. Grant’s aide, Colonel Horace Porter, wrote that he had never seen Grant so consumed, wrought up to an intensity of thought and action he seldom displayed.
But Grant gave the order, and every unit commander received sealed orders. The cavalry went first. James H. Wilson, twenty-seven years old and barely four years out of West Point, led six thousand troopers across the Chickahominy, screening everything behind them so no Confederate patrol could see what was coming.
Warren’s Fifth Corps rose from their trenches and began walking south through darkness so complete that soldiers held the coat of the man ahead to keep formation. Torchlight was forbidden near the front, and orders passed in whispers. The diversions kicked in simultaneously. Philip Sheridan’s cavalry was already two days into a raid toward Trevilian Station, designed to pull Confederate cavalry away from the James.
Butler’s forces launched probing attacks at Bermuda Hundred. And at Dutch Gap, Union engineers continued noisily cutting a canal through a bend in the James—a project that was militarily pointless but had seized Lee’s attention completely. On June 11, the day before Grant began his crossing, Lee personally visited Dutch Gap to assess the canal work. He stood on the bank of the James and believed he was looking at Grant’s plan.
He was looking at a distraction. The real operation was about to happen fifty miles away, and Lee would not understand that for four more days. The men marched through White Oak Swamp in the small hours of June 13—knee-deep mud, mosquitoes thick as fog, men collapsing from heat exhaustion even in the darkness. At dawn, Confederate scouts approached the Cold Harbor trenches and found nothing.
The positions that had held one hundred thousand Union soldiers were empty. Lee received the report and concluded that Grant was flanking south toward Richmond, the same approach every Union commander before him had attempted. It was completely wrong. He shifted his forces accordingly, placing A.
P. Hill’s corps to block the roads between the Chickahominy and the James and moving Anderson’s corps to cover White Oak Swamp and Malvern Hill. That same day, Lee wrote to Jefferson Davis with confidence: “The force I understand is engaged in cutting a canal through the neck. ” He was referring to Dutch Gap.
The truth was thirty-five miles to the east, where 115,000 men were already halfway to the James. By the evening of June 13, the lead elements of Grant’s army were approaching the river. The James at Weyanoke Point is not a gentle crossing—2,100 feet of dark tidal water, currents running two to four knots, and marshy banks offering no solid footing. On June 14 at four in the afternoon, Union engineers began building a pontoon bridge across it.
Pontoon boats, each roughly thirty feet long, were swung into the current and anchored with cables, with planking laid across them. The bridge grew foot by foot, fighting the current with every new section. By midnight, it was complete, built in eight to ten hours in tidal water by engineers who had been marching for two days without sleep. Butler had pre-sunk two vessels loaded with stone upstream to block Confederate ironclads from destroying the bridge.
Every contingency had been mapped. By the morning of June 15, roughly fifty thousand Union soldiers had already reached the south bank of the James. Hancock’s Second Corps, thirty thousand men, began crossing as the bridge groaned under artillery caissons and horses had to be blindfolded before they would step onto the swaying planks. Behind the infantry came 5,500 wagons and 28,000 animals, a single unbroken column stretching fifty miles.
The crossing proceeded for four full days without detection. The largest army in the Western Hemisphere moved fifty miles through enemy territory, crossed two major rivers, and arrived on the south bank of the James without a single Confederate commander understanding what was happening until it was far too late. Meanwhile, Lee was fighting shadows. His scouts brought contradictory reports.
His cavalry was scattered. He knew Grant had moved, but where? Richmond? The coast?
The James? Private William Fletcher of the 8th Texas Cavalry remembered the confusion across the Confederate ranks—marched and countermarched in brutal heat, sent first toward one road, then another. “We were shifted hither and yon, not knowing Grant’s game. ” Officers knew nothing, men knew less.
On June 16, reports finally reached Lee confirming a massive Union presence south of the James. The crossing was not a feint. It was the entire Army of the Potomac. Lee understood too late that Grant had stolen a march of four days and thirty-five miles.
Petersburg, the key to Richmond’s supply lines, was under immediate threat. Lee began rushing forces south, but he was forty-eight hours behind. The race for Petersburg had been lost not on the battlefield but in the four days of silence when Lee looked one direction while Grant moved in another. The vanguard of Grant’s army was already probing Petersburg’s defenses, held by a skeleton force of barely five thousand men under P.
G. T. Beauregard. What should have been a quick Union victory dissolved into confusion, missed opportunities, and broken coordination.
Attacks were late, breakthroughs were not exploited, and by the time Grant’s full force concentrated, Beauregard had scraped together fourteen thousand defenders and Lee’s reinforcements were finally on their way. The siege of Petersburg would last nine months. Lee, pinned to his defenses, could no longer maneuver. His army bled out through attrition, desertion, and starvation.
When the lines finally broke on April 2, 1865, Lee had fewer than thirty-five thousand men. A week later, at Appomattox Courthouse, he surrendered to Grant. When the last units crossed and the pontoon bridge was dismantled on June 18, the final accounting was staggering. Over ninety-six hours, 105,000 infantry, 13,000 cavalry, 4,000 artillerymen, 5,500 wagons, and 28,000 animals had crossed the James.
Union casualties during the operation were negligible—a handful of skirmishes, no major engagement, no discovery. The most vulnerable moment in the history of the Army of the Potomac, strung out over fifty miles with no ability to concentrate, passed without a single Confederate attack. Grant delivered his army to the enemy’s doorstep with a four-day head start, and though his subordinates squandered the advantage at Petersburg, the crossing itself was complete. The war of maneuver was over.
What replaced it was siege—grinding, industrial, inevitable. Grant did not defeat Lee at the James River. He made Lee irrelevant, and Lee knew it. His letters from those days reveal the realization dawning in stages: confidence on the thirteenth, uncertainty on the fourteenth, and by the sixteenth and seventeenth, urgent orders to move south, demanding cavalry reconnaissance.
The great defensive genius of the Confederacy had been reduced to chasing Grant’s shadow, four days and thirty-five miles too late. The James River still flows past Weyanoke Point. No bridge, no wagons, no army.
Just the current running 2,100 feet wide, the same as it was in June 1864, when an entire army walked across it and changed the war.