On this day, the bulk of the Army of the Potomac begins moving towards Petersburg, Virginia, precipitating a siege that lasted for more than nine months.
From early May, the Union army hounded Robert E. Lee's Army of Northern Virginia as it tried to destroy the Confederates in the eastern theater. Commanded officially by George Meade but effectively directed by Ulysses S. Grant, the Army of the Potomac sustained enormous casualties as it fought through the Wilderness, Spotsylvania, and Cold Harbor.
After the disaster at Cold Harbor, where Union troops suffered horrendous losses when they attacked fortified Rebels just east of Richmond, Grant paused for more than a week before ordering another move. The army began to pull out of camp on June 12, and on June 13 the bulk of Grant's force was on the move south to the James River. As they had done for six weeks, the Confederates stayed between Richmond and the Yankees. Lee blocked the road to Richmond, but Grant was after a different target now. After the experience of Cold Harbor, Grant decided to take the rail center at Petersburg, 23 miles south of Richmond.
By late afternoon, Union General Winfield Hancock's Second Corps arrived at the James. Northern engineers were still constructing a pontoon bridge, but a fleet of small boats began to ferry the soldiers across.
By the next day, skirmishing flared around Petersburg and the last great battle of war in Virginia began. This phase of the war would be much different, as the two great armies settled into trenches for a war of attrition.