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PA Civil War Volunteer Soldiers
Civil War Army Organization
ARMY OF THE POTOMAC - The Union Army
1 Corps = 3 Infantry Divisions and an Artillery Brigade
1 Division= 3 Brigades
1 Brigade= 4 to 6 Regiments
1 Regiment= 10 Companies (1,100 officers and men)
1 Company= 2 to 3 Platoons
1 Platoon= 5 Squads (1 officer & 50 men)
Corps was led by a Major General
Division was led by a Major General or a Brigadier General
Brigade was led by a Brigadier General
Regiment was led by a Colonel assisted by a Lieutenant Colonel and a Major
Company was led by a Captain
Platoon was led by a Lieutenant
Squad was led by a Sergeant or Corporal
Before the Civil War, the United States Army was composed of regular units. When the war broke out, state militias were called up and federalized so that the militias could serve outside of state borders and receive pay from the U.S. government. Each state had a quota of volunteer regiments for service lasting from three months to three years. See Pennsylvania Volunteer rosters and Bates' History of the Pennsylvania Volunteers for a list of PA volunteer regiments.
A regiment's flag, or "regimental colors", usually had the regiment's number and state affiliation, usually followed by "Volunteer Infantry".
The infantry was organized by regiments with ten companies to a regiment. These companies were lettered in alphabetical order A-K, with the letter "J" omitted. When the designation system was established in 1816, the letter J was omitted because it resembled the letter I in handwritten notes. In the Union Army, an infantry company had a maximum authorized strength of 101 officers and men, and a minimum strength of 83. The company was allowed to recruit a minimum of 64 or a maximum of 82 privates. In addition, each company had one captain, one first lieutenant, one second lieutenant, one first sergeant, four sergeants, eight Corporal, two musicians, and one wagoner. In the beginning of the war, company officers were elected in most volunteer units.
The artillery was also organized by regiments and each company was called a battery. A battery consisted of over 100 soldiers, armed with six cannon per battery. Batteries were assigned independently from their regiments to specific artillery brigades or to the artillery reserve of an army. The Union army had one large artillery reserve force which was an organization of extra batteries to be placed where needed.
A cavalry regiment was organized very much like the artillery. Ten to twelve companies or troops made up one regiment. The regiment was divided into three battalions, each composed of four companies. A company was divided into squadrons for easy maneuvering on the field. Each cavalryman had a carbine, saber, pistol, belt set, and equipment for his mount.
The brigade was an important organization where the regiments usually acted in cooperation with each other. The Philadelphia Brigade (69th, 71st, 72nd, 106th Pennsylvania Infantry) earned fame for withstanding the brunt of Pickett's Charge at Gettysburg. Brigades could also be composed of regiments from different states.
Each corps in the Army of the Potomac was designated by a number, I to XXV. In spring 1863, Major General Joseph "Fighting Joe" Hooker ordered the army of the Potomac to wear Corps Badges. These symbols or corps badges distinguished one corps from another. The badges were actually small cloth cut-outs shaped like crosses, spheres, stars, and quarter moons, and made in three different colors: red, white, and blue. The colors stood for the division of each corps.
The army also had a quartermaster, engineer, and signal units as well as supply wagons organized as trains. An army on the march was usually followed by miles of supply wagons loaded with food, ammunition, and medical supplies. At the top of the organizational list was the Army Headquarters. The commanding general required a personal staff to dictate orders and keep records of army movement. There were also clerks and assistants and a headquarters cook. Every army headquarters usually had staff officers, couriers, and a headquarters guard, which included an infantry battalion and a cavalry escort.
Sources: Gettysburg National Park Service, the Historical Times Illustrated Encyclopedia of the Civil War, and the Civil War Dictionary.
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