Some days after the muster, the War Department decided to accept no more regiments for three months, and gave to the men of the First Minnesota the option of enlisting for three years or taking their discharges. A considerable number, many of whom had been more patriotic than judicious, chose the latter alternative, but their places were immediately supplied, and a full regiment was mustered in for three years.
In the early morning of June 22 the regiment was paraded for the last time at Fort Snelling. Chaplain Edward D. Neill offered prayer, made an address, and gave the Hebrew benediction, “The Lord bless you and keep you,” etc. This over, the command embarked for Prairie du Chien, whence it proceeded by rail to Washington. On July 3 it was put into camp near Alexandria and attached to Franklin’s brigade of Heintzelman’s division of McDowell’s army. At the battle of Bull Run the First Minnesota was sent forward alone in support of Rickett’s battery to attack the position held by Jackson’s brigade without a single skirmisher in advance. The battery had barely unlimbered when all its horses were killed and cannoneers dispersed. The First Minnesota held its ground until forty-two men were killed and one hundred and eight wounded, the heaviest loss suffered by any regiment on the Union side. Thirty were missing, mostly prisoners, among whom were Surgeon Stewart and his assistant, Le Boutillier, who remained on the field attending the wounded. The regiment did not leave the field till ordered off, and marched “in perfect order” to Centreville. From that point to Alexandria its ranks were broken by the rabble of men and vehicles which thronged the road. In a compendious work it is impossible to follow in detail the career of this splendid regiment and those later sent out from Minnesota. It shared honorably in the operations of the Army of the Potomac in the season of 1862. At Antietam, holding its ground after both flanks had been uncovered, the First lost one hundred and forty-seven in killed and wounded. The company of Minnesota sharpshooters (the Second), added to the regiment after the battle of Fair Oaks, had twenty out of its forty-two men present shot down in that action.