Both the Union and Confederate armies utilized a modified form of the
linear tactics which defined the
French Revolutionary Wars and
Napoleonic Wars. These tactics were transmitted to American commanders in the form of manuals, the three principal ones being
Winfield Scott's
Infantry Tactics, or Rules for Manoeuvers of the United States Infantry (published in 1835),
William J. Hardee's
Rifle and Light Infantry Tactics: for the Instruction, Exercise and Maneuver of Riflemen and Light Infantry (1855), and
Silas Casey's
Infantry Tactics (1862). Other popular instruction manuals included ''McClellan's Bayonet Drill'' (1862). The core of these tactics was organizing soldiers into
ranks and
files in order to form a regiment into a
line of battle or
column. The column was primarily used for maneuvering, with a simple column consisting of companies stacked up behind one another at varying distances. More common was the double column consisting of two stacks of companies next to each other as doing so shortened the formation's length and widened its frontage.
Infantry squares were rarely employed, both because they were the most difficult formation to carry out and because they were rarely necessary on Civil War battlefields. skirmishing at
Malvern Hill Of particular tactical importance was the usage of
skirmishers, which historian Earl J. Hess argues reached its apogee during the Civil War. The textbook deployment of skirmishers was for a company to break into two platoons, one of which formed the skirmish line and the other a reserve 150 paces behind it. Soldiers deployed as skirmishers operated in groups of four known as
"comrades in battle" spaced out at five-pace intervals, with spacing of twenty to forty paces between each group. Standard practice was for two companies to form a skirmish line for a regiment, while on a larger scale a regiment would form a skirmish line for a brigade. In essence a more advanced form of the line of battle, skirmish lines nevertheless required greater individual skill and determination of the soldiers forming it. They could act as a screen for a defensive line from oncoming enemy soldiers, harassing attackers as they approached, or probed an enemy's strength in preparation for an attack and screen the assaulting force. Some regiments were more adept at skirmishing than others, but most were adequate in the role. The most common means by which an infantry attack was carried out was with multiple or successive waves of battle lines approaching the enemy. Rather than having each line be formed of regiments under one commander, the proper way was to assign sectors of the battlefield to a commander so they could form successive lines with their own regiments, thereby allowing greater command and control. Successive lines were best spaced out a couple hundred yards from each other so that they were far enough away to avoid being hit by the same fire yet close enough to provide support. The use of successive lines also necessitated an understanding how to pass one line through another, as doing so carelessly easily caused confusion. It was also common for successive lines to be organized into an
echelon formation to protect an exposed flank or outflank an opposing line. Obstacles such as buildings and ponds could be easily navigated by well-drilled units so as not to disrupt the battle lines, although linear impediments such as fences, waterways and
road cuts could be fairly disruptive. However, the presence of thick woodlands (which might account for as much as half of the area of a given Civil War battlefield) could quickly render even veteran units confused and disorganized.
Analysis Infantry tactics in the Civil War had been developed around the use of the
smoothbore musket, an inherently inaccurate weapon which (when combined with poor training and the general excitability of battle) was only effective at ranges of forty to sixty yards. For this reason emphasis was placed on
volley fire to inflict damage on the enemy. Such criticisms were picked up by later historians such as Edward Hagerman, writing that the rifled musket doomed the frontal assault and led to the introduction of
trench warfare. More recently, historians have questioned this narrative and argued these tactics remained practical. Independent studies of Civil War battle records by
Paddy Griffith,
Mark Grimsley and Brent Nosworthy found that (despite the rifled musket's superiority) infantry combat most often took place at ranges similar to those of smoothbore muskets and the causality rates were little different than from earlier wars. These were compounded by the fact that
target practice was for all intents and purposes nonexistent in both armies of the Civil War. While officers were encouraged to give their men this training, no funds were actually provided to carry them out. The result of this deficiency was readily apparent. In one instance, forty men from the
5th Connecticut fired on a fifteen-foot high barn from a distance of one hundred yards: just four actually hit the barn, and only one at a height that would have hit a man. In another, a soldier of the
1st South Carolina remarked that the chief casualties from an intense firefight conducted at one hundred yards were the needles and pinecones from the trees above them. Highly-trained
sharpshooters could utilize rifled muskets to their full potential but for most infantry a lack of training combined with the natural stresses of battle meant that the best one could do was "simply raise his rifle to the horizontal, and fire without aiming." Likewise,
Paddy Griffith also found no evidence that the elaborate earthworks of the Civil War were any more necessary to deal with modern rifle weaponry than they had been in previous wars. Instead he argues their increasing prevalence during the war was due to psychological reasons: a more risk-averse populace combined with officers influenced by the defensive-oriented teachings of men like
Dennis Hart Mahan. Hess argues that, given all these factors, the continued use of linear tactics by infantry in the Civil War were appropriate, and the most successful units were those most familiar with these tactics. An increase in volume of fire rather than range may have necessitate a change in tactics, but the
breechloader and
repeating firearms which promised to do so were simply not available in sufficient quantities until well after the war. ==Weapons and equipment==