Fitz John Porter was born in Portsmouth, New Hampshire, in 1822 into a naval family that included David Farragut and David Dixon Porter, but chose West Point, graduating eighth in 1845 and earning brevet promotions in Mexico. Commanding the Fifth Corps under George McClellan in 1862, he fought skillfully at Gaines’ Mill and Malvern Hill. This episode opens with April 1862 at Yorktown, when Porter went up alone in a hydrogen reconnaissance balloon, the tether snapped, and he drifted over Confederate lines while sketching their positions before venting gas and landing safely behind Union lines.

At Second Bull Run on August 29, 1862, John Pope ordered Porter to attack Stonewall Jackson’s flank while keeping contact with John F. Reynolds, unaware that James Longstreet’s wing stood in Porter’s path. Porter held back. The next day Longstreet’s counterattack crushed Pope’s assault, and Porter’s reserve of New York troops helped slow it. Pope accused him of insubordination, and after McClellan’s removal Porter was court-martialed and dismissed in January 1863. He spent the following decades gathering evidence, including from Confederate officers, until the Schofield Commission cleared him in 1878 and Grover Cleveland signed relief in 1886.

• Porter’s father, a naval captain, had been moved to land duty because of alcoholism.
• Pope’s single written order required Porter to attack Jackson and stay in contact with Reynolds, which the terrain made impossible.
• About 5,000 New York troops Porter held on his left took the brunt of Longstreet’s August 30 counterattack.
• After his dismissal he turned down a command in the Egyptian army and later served as New York City’s public works, police, and fire commissioner.
• Two days after Congress restored his rank in 1886, he retired voluntarily.