20th Massachusetts Infantry

Service summary:
Left State for Washington, D.C., September 4, 1861. Attached to Lander's Brigade, Division of the Potomac, to October, 1861. Lander's Brigade, Stone's (Sedgwick's) Division, Army of the Potomac, to March, 1862. 3rd Brigade, 2nd Division, 2nd Army Corps, Army of the Potomac, to March, 1864. 1st Brigade, 2nd Division, 2nd Army Corps, to July, 1865.

The 20th Massachusetts Volunteer Infantry, popularly known as the "Harvard Regiment", was one of the most honored regiments of the Army of the Potomac in the Civil War.
The Twentieth was "The Harvard Regiment" because it was officered largely by young Harvard graduates, the most famous being future Supreme Court Justice Oliver Wendell Holmes, Jr. Other notable names in the officer corps of the Twentieth include Henry L. Abbott, William Bartlett, George Nelson Macy, William Lee, Henry Ropes, Francis Palfrey, and Paul Revere, Jr. The Regiment won its fame not only from its "star" roster, however, but from hard and bloody fighting in almost all major battles fought by the Second Corps, Army of the Potomac from 1861 to 1865.

The Twentieth was in the thick of the worst fighting, from Ball's Bluff in 1861, through the Peninsula Campaign (including Fair Oaks-Seven Pines) to Antietam.

Detail Map #5: Sedgwick is Flanked in the West Woods (9-10am)

Tablet #35: Second Army Corps - 15 Sep, 7 AM to 15 Sep, 8 PM
Tablet #115: Second Army Corps - 15 Sep, 9 AM to 17 Sep, 7 AM
Tablet #120: Army of the Potomac - 17 Sep, 5 AM to 17 Sep, 12 PM
Tablet #116: Second Army Corps - 17 Sep, 6 AM to 17 Sep, 10 AM
Tablet #36: Sedgwick's Division, Second Army Corps - 17 Sep, 7 AM to 17 Sep, 10 AM
Tablet #38: Dana's Brigade, Sedgwick's Division - 17 Sep, 7 AM to 17 Sep, 12 PM

The Regiment continued to campaign with the Army of the Potomac in the savage street fighting in Fredericksburg in December 1862, to its critical role during Pickett's Charge at Gettysburg in 1863, and continuing through the Wilderness and the bloody 1864 battles.

By late 1864 it was "fought out", losing by casualties and reorganization its identity as the "Harvard Regiment". The Regiment nonetheless existed and fought as a unit to the war's conclusion at Appomattox in April 1865.

The Twentieth had the highest number of casualties among Massachusetts regiments, and of two thousand total Union regiments, it ranked fifth in casualties. The Twentieth was also labeled "The Copperhead Regiment", given the anti-abolitionist beliefs of some officers, including a significant number of the Harvard men. There was social and political conflict within the Regiment between anti-abolitionist pro-McClellan "Copperheads", and the Twentieth's abolitionists, particularly the two companies - B and C - made up largely of German immigrants.