Robert E. Lee’s Army of Northern Virginia once more reached the field of battle first and dug in at Cold Harbor before Ulysses S. Grant’s Union forces arrived in force on June 1^st. There were scattered assaults and skirmishing on June 1^st and 2^nd with significant Federal losses but the Confederate line remained unbroken.

Grant had ordered two thirds of General Butler’s Army of the James (including the 21^st Regiment C. V. Infantry)  to join his forces and they were present  for the all out assault on the Confederate line on June 3^rd. This frontal attack on heavily fortified breastworks through swamps and thickets was doomed to fail. At 4:30 AM, 60,000 Union troops attacked the Confederate position and suffered 7,000 casualties in less than one hour, most within the first eight minutes. No further assaults were made and Grant often said later in life that one of his regrets was ordering the June 3^rd assault at Cold Harbor.