On July 2, 1863, the First Minnesota Volunteer Infantry Regiment was positioned with the rest of the II Army Corps along Cemetery Ridge. As Brig. Gen. Cadmus Wilcox’s brigade approached the II Corps’ line, Corps commander Maj. Gen. Winfield Hancock ordered the single regiment to assault the oncoming Rebel brigade, a force nearly five times its size. In just five minutes of combat, roughly 82% of the Minnesota troops were either killed or wounded, including their Colonel and many of their company officers. Only 47 troops remained after the desperate struggle.
The second day at Gettysburg is still considered to be one of the deadliest days of combat for the United States military. From Little Round Top to Spangler’s Spring, possibly up to 15,000 men from both North and South laid dead or wounded on the battlefield. The next day, July 3, the fabled Confederate assault of Longstreet’s three divisions against the Union center on Cemetery Ridge occurred, skyrocketing the numbers of dead, wounded, or missing for both sides. It was not until that evening that the First Minnesota could begin evacuating their wounded and gathering the dead that had strewn the fields the day prior. With only thirty men remaining to gather the wounded and fallen, the First Minnesota was able to recover nearly all of them.
Below, are two excerpts of accounts of survivors of the regiment gathering the wounded on July 3 and July 4:
“After nightfall, very many of the men temporarily joined the ambulance corps to assist their wounded comrades. A beautiful full moon shone over the battlefield in the earliest part of the night, and it was comparatively easy to find the stricken heroes; the wounded were all found and gathered up but six and sent to the Leitner house ad orchard and the other field hospitals east of Cemetery Ridge. The six men were reported by Captain Coates as missing, but they were finally found where they had crawled into thickets and other retreats and become unconscious or fallen asleep. Then their records were changed from “missing” to “wounded.” Nearly every dead man was left on the field where he fell until July 4; a few were buried by company comrades before morning […] And near where they fell, in the beautiful National Cemetery, are still the last bivouacs of the First Minnesota.” 
“But no one, though but moderately endowed with common sense and no more than the ordinary amount of compassion in his make-up, could fail to sympathize, deeply, with the overwhelming amount of suffering that existed and which they were powerless to relieve. Tens of thousands were suffering from wounds, many were dying every hour; and many still living considered those already dead more fortunate than themselves.” 
1. History of the First Minnesota Volunteer Infantry 1861-1864 (Stillwater, MN: Easton & Masterman), 346-347.
2. Account by James Wright, First Minnesota Infantry, in Brian Leehan, Pale Horse at Plum Run: The First Minnesota at Gettysburg (St. Paul: Minnesota Historical Society, 2002), 105.