The regiment is best known for the dramatic charge at the battle of Gettysburg. On the evening of July 2, 1863 the regiment attacked Wilcox's Alabama Brigade as it was preparing for the final push to break the Union line. Confederate General Wilcox stated in his report, "This stronghold of the enemy, together with his batteries, were almost won, when still another line of infantry descended the slope in our front at a double-quick, to the support of their fleeing comrades and for the defense of the batteries." The line of infantry was the First Minnesota. They crossed over 200 yards of open ground and charged the Confederates in spite of five to one odds. The rebels recovered and in five minutes killed or wounded over 170 of the 300 plus men. The survivors did not panic but fell back to their orginal position and rallied around the remnant of the flag waiting for a counterattack that did not come.
The reduced regiment fought as skirmishers at the battle of Bristoe Station and mustered out in May 1864. The First Battalion was created with veterans of the regiment who reenlisted or had more time to serve and this unit saw heavy action at Petersburg and Appomattox.
After the war the survivors held annual reunions in Minneapolis and St. Paul where they reminisced and took up collections to help members in need. These reunions continued until 1932; the last members of the regiment, Edwin Season and James Wright of Company F died in 1936.