Heavy infantry

Heavy infantry consisted of heavily armed and armoured infantrymen who were trained to mount frontal assaults and/or anchor the defensive center of a battle line. This differentiated them from light infantry who are relatively mobile and lightly armoured skirmisher troops intended for screening, scouting, and other tactical roles unsuited to soldiers carrying heavier loads. Heavy infantry typically made use of dense battlefield formations, such as shield wall or phalanx, multiplying their effective weight of arms with force concentration.

Heavy infantry were critical to many ancient armies, such as the Greek hoplites, Macedonian phalangites, and Roman legionaries. After the fall of Rome, heavy infantry declined in Europe but returned to dominance in the Late Middle Ages with Swiss pikemen and German Landsknechts. With the rise of firearms during early modern warfare, dense formations became increasingly hazardous, and heavy armours were either ineffective or too cumbersome to be tactically useful. By the early 18th century, heavy infantry were replaced by line infantry armed with muskets and bayonets and wore no armour.