On the evening of April 1, 1865, Lieutenant General Ulysses S. Grant ordered a massive attack against the Confederate lines defending Petersburg for the following morning. In the pre-dawn darkness of April 2, the Union Sixth Corps formed in a wedge-shaped formation and attacked the Confederate works directly ahead at 4:30 a.m., crossing one-half mile of open fields within minutes. Soldiers from North Carolina met the assault with musket and cannon fire, inflicting hundreds of casualties in about fifteen minutes, but the Union attackers pressed on, climbed over the earthworks, and fought a vicious hand-to-hand struggle along the line. The outnumbered Confederates could not hold their position; many were captured, and unknown numbers of others were killed or wounded. Union flags soon flew over ramparts long defended by General Robert E. Lee’s troops. This breakthrough forced Lee to evacuate Petersburg that night, led Confederate government officials to flee Richmond as well, and preceded Lee’s surrender to Grant at Appomattox Court House one week later.