Infantry (or foot-soldiers) was the main building block of both Union and Confederate armies. The infantrymen traveled from place to place by marching on foot, with some exceptions when they were transported by boat or train. They fought with small arms and were supported by cavalry, artillery, engineers, signal corps, hospital corps, commissary and other agencies or branches.
Here’s some recommended reading for detailed information on Civil War Infantry.
Artillery (cannon) have played an important role in warfare for centuries before the Civil War. They are typically broken up into three categories: siege artillery, field artillery and naval artillery. As it pertains to Gettysburg, both armies used field artillery with a variety of types of gun. The two main classes were rifled (also called “guns”) and smoothbore and within those classes were a variety of models, the most common being the 3 inch Ordinance Rifle and smoothbore Napoleon. All types of artillery fired a variety of ordinance (ammunition). They are solid shot (or bolt), case shot (or shrapnel and canister (or grape shot, which was a naval round that was not used in the field but this term was often used interchangeably with canister shot).
Cavalry was the branch of the army mounted on horseback. Being that it was mounted, it was able to get from point A to point B quicker than infantry and armed with lighter, short-range firearms, cavalry’s main roles were as follows:
• Reconaissance and screening
• defensive/delaying actions (like Buford’s Cavalry on the first day at Gettysburg)
• “mopping up the field” when an enemy infantry is shaken or routed
• offensive actions like charging an enemy’s flank or rear while it is engaged with friendly infantry
• long distance raids on enemy bases of supply or supply lines
When the Civil War began, cavalry was a lost child. It had its use, but cirumstances made it so that its use wasn’t fully realized or evolved until the war was underway. Confederates seemed to make better use of it early in the war, but the United States Army finally brought cavalry into its own after the batle of Chancellorsville at the battle of Brandy Station, Virginia.
Recommended reading for more detailed information on the cavalry at Gettysburg.
Army engineers were vital to the movement and defense of an army or territory. They moved the army over rivers and streams with pontoon bridges, protected them with earthworks during long operations like a siege; sometimes used hydrogen-filled balloons to survey battlefields and make maps, performed skirmish duties, bridge guards and designed and constructed a ring of forts around Washington D.C.
The signal corps was responsible for communications over great distances for the army to relay tactical and strategic messages by utilizing telegraphs and “wig-wag” flags. In the Union army, the signal corps had the duties of battlefield observation, intelligence gathering and directing artillery fire from elevated positions on which they established signal stations. In the Confederate Army, the signal corps shared those duties but was also used for espionage.
Recommended reading for more detailed information on Civil War Signal Corps.