 During this campaign , the 21st suffered heavy casualties during the Battle of Spotsylvania and the Battle of Bethesda Church . In the latter engagement , the 21st acted as rear guard and bore the brunt of a fierce attack but held their position . Grant 's Overland Campaign concluded with several assaults on Petersburg , Virginia , on June 15 – 18 , 1864 . The 21st again took considerable casualties during these attacks , particularly during the assault on June 17 . Maj. Henry Richardson , commanding the 21st , was wounded in the thigh during the engagement and was shortly thereafter sent home . Now numbering less than 100 men , the regiment had been reduced to a tenth of its original size . Company A , by this time , had only three men on its active roster . 
