The Union victory along the White Oak Road on March 31st threatened to destabilize the entire Confederate line west of Petersburg. General Robert E. Lee ordered Maj. Gen. George Pickett with his infantry division and the cavalry divisions of Col. Thomas Munford, Maj. Gen. W.H.F. Lee, and Maj. Gen Thomas Rosser to hold the vital crossroads of Five Forks, along the White Oak Road five miles west of the previous fighting there. Pickett's defensive line was not well constructed, and much of his cavalry force was posted in wooded areas where it was difficult to maneuver. On the afternoon of April 1st, while Maj. Gen. Phil Sheridan’s Union cavalry under Maj. Gen. Wesley Merritt pinned the right flank of the Confederate force in position, the Fifth Corps under Maj. Gen. Gouverneur K. Warren attacked and overwhelmed the Confederate left flank, taking many prisoners. Sheridan personally directed portions of the Fifth Corps attack, while Pickett was absent from the front having a lunch when Warren's men struck. The last part of the Confederate line to collapse was the center at the road junction, held by artillery until overrun by Union cavalry. Young Colonel “Willie” Pegram, beloved Confederate artillery officer, was mortally wounded there. The loss of Five Forks threatened Lee’s last supply line, the South Side Railroad. The next morning, Lee informed President Jefferson Davis that Petersburg and Richmond must be evacuated.