Confederate General Robert E. Lee's supply line into Petersburg, Virginia, is closed when Union forces under General Ulysses S. Grant collapse the end of Lee's lines around Petersburg. The Confederates suffer heavy casualties, and the battle triggered Lee's retreat from Petersburg as the two armies began a race that would end a week later at Appomattox Court House.
For nearly a year, Grant had laid siege to Lee's army in an elaborate network of trenches that ran from Petersburg to the Confederate capital at Richmond, 25 miles north. Lee's hungry army slowly dwindled through the winter of 1864-65 as Grant's army swelled with well-fed reinforcements. On March 25, Lee attacked part of the Union trenches at Fort Stedman in a desperate attempt to break the siege and split Grant's force. When that attack failed, Grant began mobilizing his forces along the entire 40-mile front. Southwest of Petersburg, Grant sent General Philip Sheridan against Lee's right flank.
Sheridan moved forward on March 31, but the tough Confederates halted his advance. Sheridan moved troops to cut the railroad that ran from the southwest into Petersburg, but the focus of the battle became Five Forks, a road intersection that provided the key to Lee's supply line. Lee instructed his commander there, General George Pickett, to "Hold Five Forks at all hazards." On April 1, Sheridan's men slammed into Pickett's troops. Pickett had his force poorly positioned, and he was taking a long lunch with his staff when the attack occurred. General Gouverneur K. Warren's V Corps supported Sheridan, and the 27,000 Yankee troops soon crushed Pickett's command of 10,000. The Union suffered 1,000 casualties, but nearly 5,000 of Pickett's men were killed, wounded, or captured. During the battle, Sheridan, with the approval of Grant, removed Warren from command despite Warren's effective deployment of his troops. It appears that a long-simmering feud between the two was the cause, but Warren was not officially cleared of any wrongdoing by a court of inquiry until 1882.
The vital intersection was in Union hands, and Lee's supply line was cut. Grant now attacked all along the Petersburg-Richmond front and Lee evacuated the cities. The two armies began a race west, but Lee could not outrun Grant. The Confederate leader surrendered at Appomattox Court House, Virginia, on April 9.