Civil War Union Brevet Brigadier General. A Harvard law student when the Civil War broke out, he joined the 4th Battalion of the Massachusetts Militia after the Confederates fired on Fort Sumter, South Carolina. However, in August 1861, at the age of 19, he was commissioned a 2nd Lieutenant in the 20th Massachusetts Volunteer Infantry, which was known as the "Harvard Regiment" because most of its officers were either students or graduates of Harvard University. The regiment became one of the famous units in the Union Army of the Potomac, and contained such luminaries as future Supreme Court Justice Oliver Wendell Holmes Jr., future Union General William F. Bartlett, and future Union Brevet Generals Paul J. Revere, George N. Macy, Henry Patten, Francis Palfrey and William R. Lee. Henry L. Abbott saw action in every battle the regiment participated in up to the 1864 Battle of the Wilderness. He fought at the October 1861 debacle at Balls Bluff, Virginia, in the Spring 1862 Peninsular Campaign, the bloodshed at Antietam (where the 20th Massachusetts lost 124 men in the disaster that befell General John Sedgwick's Division in the West Woods) and at Fredericksburg in December 1862. In the Battle of Fredericksburg, he commanded a portion of his unit that crossed the river on pontoons the day before the main battle, and became embroiled in brutal street fighting along Caroline Street, where they stood heroically under fire and battled the Mississippians of General William Barksdale's Brigade, who were charged with defending the town. His bravery that day won particular praise from his comrades and commanding officers. In the July 1863 Battle of Gettysburg, his regiment took part in the repulse of Pickett's Charge and he assumed command when Colonel Paul Revere was mortally wounded by an artillery shell and Lieutenant Colonel George Macy was wounded. He was advanced to Major, and remained 2nd in command when Colonel Macy returned from his wounds. In the 1864 Overland Campaign, he was with the 20th Massachusetts during the third day of the Battle of the Wilderness when they were suddenly taken unaware by the onrush of attacking South Carolina troops. He again assumed command when Colonel Macy was wounded, and refused to lie down in an effort to inspire and steady his men. Soon after he was shot and mortally wounded, with his men dragging him to the rear before they themselves retreated. He lived only a few minutes more before dying, and was specially mentioned and lamented by brigade commander General Alexander Webb, Division commander General John Gibbon and Corps commander General Winfield Scott Hancock in their after battle reports. His remains were taken back to his hometown of Lowell, Massachusetts. On March 13, 1865 he received a posthumous brevet promotion to Brigadier General, US Volunteers for "gallant and meritorious services in the battle of the Wilderness". Years later he was often eulogized by his former comrades, and was specifically honored by Oliver Wendell Holmes in his Memorial Day 1885 "Hearts Touched With Fire" speech. He was the son of Judge and Congressman Josiah Gardner Abbott. His older brother, Edward "Ned" Abbott, served as a Captain in the 2nd Massachusetts Volunteer Infantry, and was killed in the Battle of Cedar Mountain. In 1991, Major Abbott's letters home were edited by historian Robert Scott Garth and were published as "Fallen Leaves: The Civil War Letters of Major Henry Livermore Abbott".