Heavy infantry

Heavy infantry refers to heavily armed and armoured infantrymen trained to mount frontal assaults and/or anchor the defensive center of a battle line. This differentiates them from medium or light infantry which are relatively mobile and lightly armoured skirmisher troops intended for screening, scouting, and other roles unsuited to the heavier soldiers.

The concept of heavy infantry has been made largely obsolete by 20th century advances in battlefield tactics, small arms and body armor technology which have produced a more consolidated role for the infantryman. As such, the term "heavy infantry" almost always refers to pre-Gunpowder Age troops.

In ancient Greece the Hoplite was a common form of heavy infantry. All hoplites had a shield and spear, and perhaps a helmet as well. Wealthier hoplites were able to afford bronze breastplate or linothorax armor, while poorer hoplites wore little to no armor. The hoplite armor and shield were designed to block arrows and blows from spear points and swords. Hoplites would act as both a city watch and as an army in the field. Hoplites were thought of as a force to be reckoned with because they would form a phalanx, a tight band of spearmen, which aided them against lighter infantry and cavalry.

Herodotus has described an elite heavy infantry unit of 10,000 soldiers, which he called the Immortals, in the army of the Achaemenid Empire. They were reportedly carrying wicker shields, short spears, quivers, swords or large daggers, slings, and bow and arrow. Underneath their robes they wore scale armour coats. The regiment was followed by a caravan of covered carriages, camels, and mules that transported their special supplies.

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