Although Porter served well in the early battles of the Civil War, his military career was ruined by the controversial trial, which was called by his political rivals. After the war, he worked for almost 25 years to restore his tarnished reputation and was finally restored to the army's roll.
Porter was promoted to second lieutenant on June 18, 1846, and First Lieutenant on May 29, 1847. He served in the Mexican–American War and was appointed a brevet captain on September 8, 1847, for bravery at the Battle of Molino del Rey. He was wounded at Chapultepec on September 13, for which he also received a brevet promotion to major.[4] He was an original member of the Aztec Club of 1847, a military society composed of officers who served during the Mexican War, and presided over it from 1892 to 1893.
After the war with Mexico ended, Porter returned to West Point and became a cavalry and artillery instructor from 1849 to 1853. He served as adjutant to the academy's superintendent until 1855. He next was posted to Fort Leavenworth, Kansas, as assistant adjutant general in the Department of the West in 1856; he was brevetted to captain at Fort Leavenworth that June. Porter served under future ConfederateAlbert Sidney Johnston in the expedition against the Mormons in 1857 and 1858. Afterward, Porter inspected and reorganized the defenses of Charleston Harbor, South Carolina, until late 1860, when he aided the evacuation of military personnel from Texas after that state seceded from the Union.[5]
American Civil War
After the start of the Civil War, Porter became chief of staff and assistant adjutant general for the Department of Pennsylvania, but he was soon promoted to colonel of the 15th Infantry on May 14, 1861. General John A. Logan, Porter's later political nemesis, would accuse Porter of helping persuade his commander Robert Patterson to let Joseph E. Johnston's force escape out of the Shenandoah Valley and reinforce P. G. T. Beauregard, thus turning the tide at the First Battle of Bull Run.[6] In August, Porter was promoted to brigadier general of volunteers, backdated to May 17[4] so he would be senior enough to receive divisional command in the Army of the Potomac, newly formed under Maj. Gen.George B. McClellan. Soon Porter became a trusted adviser and loyal friend to McClellan, but his association with the soon-to-be-controversial commanding general would prove to be disastrous for Porter's military career.
In addition, Porter had a memorable experience when he decided to make aerial observations in a hot air balloon without the assigned expert to handle the craft, Professor Thaddeus Lowe. When he ascended with only one securing line, the balloon subsequently broke loose and General Porter found himself drifting west over enemy lines in danger of being captured or killed. Fortunately, the combination of a favorable wind change and himself adjusting the gas valves allowed Porter to return to the Union lines and land safely.[8] Although it was an embarrassing accident, General Porter was able to perform his observations of enemy defences as intended and recorded his findings, although the balloon program was disbanded a year later.[9]
For his successful performance on the peninsula, he was promoted to major general of volunteers on July 4, 1862.[4]
Second Bull Run
Porter's corps was sent to reinforce Maj. Gen. John Pope in the Northern Virginia Campaign, a reassignment that he openly challenged and complained about, criticizing Pope personally. During the Second Battle of Bull Run, on August 29, 1862, he was ordered to attack the flank and rear of Maj. Gen. Thomas J. "Stonewall" Jackson's wing of the Army of Northern Virginia. Porter had stopped at Dawkin's Branch, where he had encountered Maj. Gen. J.E.B. Stuart's cavalry screen. On August 29 he received a message from Pope directing him to attack the Confederate right (which Pope assumed to be Jackson on Stony Ridge), but at the same time to maintain contact with the neighboring division under Maj. Gen. John F. Reynolds, a conflict in orders that could not be resolved. Pope was apparently unaware that Confederate Maj. Gen. James Longstreet's wing of the opposing army had arrived on the battlefield; the proposed envelopment of Jackson's position would have collided suicidally with Longstreet's large force. Porter chose not to make the attack because of the intelligence he had received that Longstreet was to his immediate front.
On August 30 Pope again ordered the flank attack, and Porter reluctantly complied. As the V Corps turned to head towards Jackson's right and attacked, it presented its own (and consequently the entire army's) flank to Longstreet's waiting men. About 30,000 Confederates assailed Porter's 5,000 or so men, driving through them and into the rest of Pope's forces, doing exactly what Porter most feared would come of these orders. Pope was infuriated by the defeat, accused Porter of insubordination, and relieved him of his command on September 5.[10]
Porter was soon restored to command of the corps by McClellan and led it through the Maryland Campaign, where the corps served in a reserve position during the Battle of Antietam. He is said to have told McClellan, "Remember, General, I command the last reserve of the last Army of the Republic."[11] McClellan took his implied advice and failed to commit his reserves into a battle that might have been won if he had used his forces aggressively.
On November 25, 1862, Porter was arrested and court-martialed for his actions at Second Bull Run. By this time, McClellan had been relieved by PresidentAbraham Lincoln and could not provide political cover for his protégé. Porter's association with the disgraced McClellan and his open criticism of Pope were significant reasons for his conviction at court-martial. Porter was found guilty on January 10, 1863, of disobedience and misconduct, and he was dismissed from the Army on January 21, 1863.[12]
In describing the Battle of Second Manassas, Edward Porter Alexander wrote that Confederates who knew Porter respected him greatly and considered his dismissal "one of the best fruits of their victory".[13]
Later life and death
After the war ended, Porter was offered a command in the Egyptian Army but declined it.[10] He spent most of the remainder of his public life fighting against the perceived injustice of his court-martial.
In 1878, a special commission under General John Schofield exonerated Porter by finding that his reluctance to attack Longstreet probably saved Pope's Army of Virginia from an even greater defeat. Eight years later, President Grover Clevelandcommuted Porter's sentence and a special act of the U.S. Congress restored Porter's commission as an infantry colonel in the U.S. Army, backdated to May 14, 1861, but without any back pay due. Two days later, August 7, 1886, Porter, seeing vindication, voluntarily retired from the Army.
Porter was involved in mining, construction, and commerce. He was appointed as the New York City Commissioner of Public Works, the New York City Police Commissioner, and the New York City Fire Commissioner.
On December 27, 1894, Porter, along with 18 others, founded the Military and Naval Order of the United States, which was soon renamed the Military Order of Foreign Wars. Porter's name was at the top of the list of signers of the original institution and received the first insignia issued by the Order.
^Eicher & Eicher, p. 435. Court-martialed 1863, restored and resigned in 1886 to rank from 1861
^Wayne Soini (2011). Porter's Secret: Fitz John Porter's Monument Decoded. Portsmouth, NH: Peter E. Randall Publisher. pp. 9–11. ISBN978-0-9828236-8-2.
Eisenschiml, Otto, The Celebrated Case of Fitz John Porter: An American Dreyfus Affair, Indianapolis, IN: Bobbs-Merrill, 1950.
Hennessy, John J. Return to Bull Run: The Campaign and Battle of Second Manassas. Norman: University of Oklahoma Press, 1993. ISBN0-8061-3187-X.
Soini, Wayne. Porter's Secret: Fitz John Porter's Monument Decoded. Portsmouth, New Hampshire: Jetty House an imprint of Peter E. Randall Publisher, 2011. ISBN978-0-9828236-8-2.
Paleno, Gene. "The Porter Conspiracy, A story of the Civil War", PAL Publishing, Upper Lake CA (ISBN978-0-9894847-4-9)