The Battle of Cold Harbor was fought during the American Civil War near Mechanicsville, Virginia, from May 31 to June 12, 1864, with the most significant fighting occurring on June 3. It was one of the final battles of Union Lt. Gen. Ulysses S. Grant's Overland Campaign, and is remembered as one of American history's bloodiest, most lopsided battles. Thousands of Union soldiers were killed or wounded in a hopeless frontal assault against the fortified positions of Confederate Gen. Robert E. Lee's army.

​

On May 31, as Grant's army once again swung around the right flank of Lee's army, Union cavalry seized the crossroads of Old Cold Harbor, about 10 miles northeast of the Confederate capital of Richmond, Virginia, holding it against Confederate attacks until the Union infantry arrived. Both Grant and Lee, whose armies had suffered enormous casualties in the Overland Campaign, received reinforcements. On the evening of June 1, the Union VI Corps and XVIII Corps arrived and assaulted the Confederate works to the west of the crossroads with some success.

​

On June 2, the remainder of both armies arrived and the Confederates built an elaborate series of fortifications 7 miles long. At dawn on June 3, three Union corps attacked the Confederate works on the southern end of the line and were easily repulsed with heavy casualties. Attempts to assault the northern end of the line and to resume the assaults on the southern were unsuccessful.

Grant said of the battle in his Personal Memoirs, "I have always regretted that the last assault at Cold Harbor was ever made. ... No advantage whatever was gained to compensate for the heavy loss we sustained." The armies confronted each other on these lines until the night of June 12, when Grant again advanced by his left flank, marching to the James River. In the final stage, Lee entrenched himself within besieged Petersburg before finally retreating westward across Virginia.

​

Some authors (Catton, Esposito, Foote, McPherson, Grimsley) estimate the casualties for the major assault on June 3 and all agree on approximately 7,000 total Union casualties, 1,500 Confederate. Gordon Rhea, considered the preeminent modern historian of Grant's Overland Campaign, has examined casualty lists in detail and has published a contrarian view in his 2002 book, Cold Harbor. For the morning assault on June 3, he can account for only 3,500 to 4,000 Union killed, wounded, and missing, and estimates that for the entire day the Union suffered about 6,000 casualties, compared to Lee's 1,000 to 1,500. Rhea noted that although this was a horrific loss, Grant's main attack on June 3 was dwarfed by Lee's daily losses at Antietam, Chancellorsville, and Pickett's Charge, and is comparable to Malvern Hill.

​

The battle caused a rise in anti-war sentiment in the Northern states. Grant became known as the "fumbling butcher" for his poor decisions. It also lowered the morale of his remaining troops. But the campaign had served Grant's purpose—as ill-advised as his attack on Cold Harbor was, Lee had lost the initiative and was forced to devote his attention to the defense of Richmond and Petersburg. He beat Grant to Petersburg, barely, but spent the remainder of the war (save its final week) defending Richmond behind a fortified trench line. Although Southerners realized their situation was desperate, they hoped that Lee's stubborn (and bloody) resistance would have political repercussions by causing Abraham Lincoln to lose the 1864 presidential election to a more peace-friendly candidate. The taking of Atlanta in September dashed these hopes, and the end of the Confederacy was just a matter of time.

 

In 2008, the Civil War Trust (a division of the American Battlefield Trust) placed the Cold Harbor battlefield on its Ten Most Endangered Battlefields list. Development pressure in the Richmond area was so great that only about 300 acres (1.2 km2) of what was once at least a 7,500-acre (30 km2) battlefield are currently preserved as part of the Richmond National Battlefield Park. Hanover County also maintains a small 50 acre park adjacent to the NPS's Cold Harbor holdings.The Trust and its partners have acquired and preserved 250 acres (1.0 km2) of the battlefield through late 2021.