Wilderness campaign, in the American Civil War, a series of engagements (May–June, 1864) fought in the Wilderness region of Virginia. Early in May, 1864, the Northern commander in chief, Grant, led the Army of the Potomac (118,000 strong) across the Rapidan River into the Wilderness, a wild and tangled woodland c.10 mi (16 km) W of Fredericksburg. Grant planned to clear the Wilderness before trying to destroy the smaller Confederate Army of Northern Virginia (60,000 troops) under Robert E. Lee. But Lee advanced on the Union troops while they were still in that area, causing Grant to face about and order an attack. The nature of the terrain made the battle of the Wilderness (May 5–6) a disjointed but bloody fight. After the repulse of a Union attack on May 6 through the opportune arrival of the 1st Corps under James Longstreet, Lee counterattacked, and the battle became stabilized. Grant then pushed ahead by Lee's right, heading toward Spotsylvania Courthouse, c.12 mi (19 km) to the southeast. Lee, anticipating the move, was soon entrenched there. In the battle of Spotsylvania Courthouse (May 8–19), Grant unsuccessfully hammered away at the Confederate lines. The bloodiest fighting of this battle occurred on May 12 when the Union assault on the salient forming the Confederate center (the Bloody Angle) was repulsed after initial success. Lee confronted Grant's next move from a position S of the North Anna River, so impregnable that even Grant did not attack. By the beginning of June both armies were near Richmond. Fearing that Lee might withdraw within the defenses of the capital, Grant made another unsuccessful frontal assault on his strongly entrenched enemy in the battle of Cold Harbor, June 3, 1864. The Union lost 7,000 men in a few hours—the most horrible slaughter of the war. After several days of desultory trench fighting Grant then withdrew, crossed the James River, and moved against Petersburg. He had lost about 60,000 men in the campaign, and although Lee's army sustained the proportionately larger loss of 20,000, it was by no means destroyed.
See C. Dowdy, Lee's Last Campaign (1960); E. Steere, The Wilderness Campaign (1960, repr. 1987).