Saturday, June 18, 1864
General Winfield S. Hancock, still suffering from the ill effects of his wound at Gettysburg, was no longer able to remain in command of the Second Corps. General David Birney was named as his temporary replacement.
General Byron Root Pierce, the commander of the First Brigade of General John Gibbon’s Second Division of the Second Corps, assumed his new role after the mortal wounding of First Brigade Generals Harry Boyd McKeen and Frank Haskell on June 3 at Cold Harbor. At 5:00 A.M. General Pierce's brigade was ordered to attack the Confederate earthworks at Petersburg. General George Meade received an intelligence report that the Confederates had withdrawn to an undisclosed location closer to Petersburg. The assault on the outer works confirmed that the report was indeed true, as the earthworks had been abandoned. Meade ordered General Birney to advance, and the new Confederate line was soon revealed to be located behind a sunken road. After two unsuccessful charges to break the Confederate line the Twentieth Massachusetts dug trenches for a prolonged assault.1
1Richard F. Miller, Harvard's Civil War: A History of the Twentieth Massachusetts Volunteer Infantry (Lebanon, New Hampshire: University Press of New England, 2005), 387-90.