Although he had a very similar name to our last subject, Philip St. George Cooke was dissimilar in that even though he was a native Virginian he remained loyal to the Union. Cooke was most often associated with the cavalry having written an Army cavalry manual. He is sometimes called the “Father of the U.S. Cavalry.” But his service to the Union, although significant, was eclipsed by that of his more famous son-in-law, J.E.B. Stuart.
Philip St. George Cooke was born in Leesburg, Virginia on June 13, 1809. Graduating from West Point in 1827, he was commissioned a second lieutenant in the infantry. He served on a number of frontier posts in the West and fought in the Black Hawk War. In 1833, he was promoted to first lieutenant and assigned to the newly-formed United States Regiment of Dragoons which would become the 1st U.S. Dragoons in 1836.
The word dragoon originally meant mounted infantry, who were trained in horse riding as well as infantry fighting skills. However, usage altered over time and during the 18th century, dragoons evolved into conventional light cavalry units and personnel. The name is possibly derived from a type of firearm (called a dragon) carried by dragoons of the French Army.
Cooke served throughout the West in the years before the Civil War. During the Mexican-American War he led the Mormon Battalion from Santa Fe to California, receiving a brevet promotion to lieutenant colonel for his service in California. In the 2nd U.S. Dragoons he defeated the Jicarilla Apache in Ojo Caliente, New Mexico in 1854.
He was in the 1855 Battle of Ash Hollow against the Sioux. He was sent to keep the peace in Bleeding Kansas in 1856 – 1857. Acquainted with Brigham Young, Cooke took part in the Utah expedition of 1857–58, after which he was promoted to colonel and assigned command of the 2nd U.S. Dragoons. He was an observer for the U.S. Army in the Crimean War, and commanded the Department of Utah from 1860 until 1861.
The issue of secession deeply divided the Cooke family. Although he remained loyal to the Union his son, John Rogers Cooke, joined the Confederate Army, eventually commanded an infantry brigade in the Army of Northern Virginia and was wounded seven times in the service of the Confederacy.
His more famous son-in-law, J.E.B. Stuart, was never reconciled to Cooke and said about his father-in-law’s loyalty to the Union: “He will regret it only once, and that will be continually.” Stuart had met and married Flora Cooke in 1855. Of Flora, it was written the she was “an accomplished horsewoman, and though not pretty, an effective charmer,” to whom “Stuart succumbed with hardly a struggle.”
At the start of the war, the Union Army had five regiments of cavalry. Cooke’s unit, the 2nd Dragoons, was redesignated the 2nd U.S. Cavalry. Cooke had written a new cavalry manual in 1858 but the War Department did not publish it until 1862.
Cooke believed in mounted attacks as the primary use of cavalry but the adoption of the rifled musket as an infantry weapon made the classic cavalry charge essentially obsolete and recommended a mission emphasis on reconnaissance and screening.
A prominent theory of cavalry charges at the time, endorsed by future generals Henry W. Halleck and George B. McClellan, was that the cavalry should be deployed in double ranks (a regiment would deploy in two lines of five companies each), which would increase the shock effect of the charge by providing an immediate follow-up attack.
Cooke’s manual called for a single-rank formation in which a battalion of four companies would form a single line and two squadrons of two companies each would cover the flanks. A third battalion would be placed in reserve a few hundred yards to the rear. Cook believed that the double-rank offensive promoted disorder of the horses in the ranks and would be difficult to control.
Cooke was appointed a brigadier general in November 1861. At first, he commanded a brigade of regular Army cavalry headquartered in Washington as part of the defenses there. For the Peninsula Campaign he was given the command of the Army of the Potomac’s Cavalry Reserve, a division-size formation. The Reserve had two brigades with three regiments each.
Cooke was sent along with Major General George Stoneman in pursuit of Confederate forces that had evacuated Yorktown. His cavalry was roughed up in an assault ordered by Stoneman against Fort Magruder. He saw subsequent action at the battles of Williamsburg, Gaines’ Mill, and White Oak Swamp. Cooke ordered an ill-fated charge of the 5th U.S. Cavalry at Gaines’ Mill during the Seven Days Battles, sacrificing nearly an entire regiment of regulars.
After the Peninsula Campaign, Cooke left active duty service. One reason that has been given was his son-in-law’s humiliation of the Union cavalry by completely encircling the Army of the Potomac in his celebrated raid.
Stuart had set out with 1,200 troopers on the morning of June 12 and, having determined that the flank was indeed vulnerable, took his men on a complete circumnavigation of the Union army, returning after 150 miles on July 15 with 165 captured Union soldiers, 260 horses and mules, and various quartermaster and ordnance supplies. His men met no serious opposition from the more decentralized Union cavalry, commanded by his father-in-law.
Cooke served on boards of court-martial, commanded the District of Baton Rouge, and was superintendent of Army recruiting for the Adjutant General’s office. On July 17, 1866, President Andrew Johnson nominated Cooke for appointment to the brevet grade of major general in the regular army, to rank from March 13, 1865, and the U.S. Senate confirmed the appointment on July 23, 1866.
Cooke commanded the Department of the Platte from 1866 to 1867, the Department of the Cumberland from 1869 to 1870, and the Department of the Lakes. He retired from the Army with almost 50 years service on October 29, 1873 as a brigadier general. Cooke died in Detroit, Michigan, and is buried there in Elmwood Cemetery.