He is remembered for an eloquent letter he wrote to his wife Sarah a week before he was mortally wounded in the First Battle of Bull Run.

[3] After the bombardment of Fort Sumter in April 1861, President Lincoln called on the States loyal to the Union to provide 75,000 militia troops.

After training at Camp Clark in Washington D.C., the 2nd Rhode Island had joined the Union Army of Northeastern Virginia by July 1861.

The 2nd Rhode Island Infantry were in the Second Brigade under the command of Colonel Ambrose Burnside and were part of the Second Division in the Union Army of Northeastern Virginia.

During a Confederate attack at Bull Run, Ballou was hit by a six-pounder cannonball which tore off part of his right leg and killed his horse.

[1][6] In place of his body, some charred ash and bone from Sudley were reburied in Swan Point Cemetery in Providence, Rhode Island.

[3] Ballou's now-famous letter to his beloved 24-year-old wife, Sarah, endeavored to express the emotions he was feeling on the eve of battle against the Confederacy: worry, fear, guilt, and sadness, while at the same time conveying his undying love for her and his children and his desire to fulfil his sense of duty to his nation.

I know how strongly American Civilization now leans upon the triumph of the Government, and how great a debt we owe to those who went before us through the blood and suffering of the Revolution.

But, my dear wife, when I know that with my own joys I lay down nearly all of yours, and replace them in this life with cares and sorrows—when, after having eaten for long years the bitter fruit of orphanage myself, I must offer it as their only sustenance to my dear little children—is it weak or dishonorable, while the banner of my purpose floats calmly and proudly in the breeze, that my unbounded love for you, my darling wife and children, should struggle in fierce, though useless, contest with my love of country.

And hard it is for me to give them up and burn to ashes the hopes of future years, when God willing, we might still have lived and loved together and seen our sons grow up to honorable manhood around us.

I must watch you from the spirit land and hover near you, while you buffet the storms with your precious little freight, and wait with sad patience till we meet to part no more.

If the dead can come back to this earth and flit unseen around those they loved, I shall always be near you; in the brightest day and in the darkest night—amidst your happiest scenes and gloomiest hours—always, always; and if there be a soft breeze upon your cheek, it shall be my breath; or the cool air fans your throbbing temple, it shall be my spirit passing by.

[9] The letter was featured prominently in Ken Burns' 1990 award-winning documentary The Civil War, where an abridged version was read by Paul Roebling in a pairing with Jay Ungar's musical piece "Ashokan Farewell".