Infantry is a specialization of military personnel who engage in ground combat on foot. Infantry generally consists of light infantry, irregular infantry, heavy infantry, mountain infantry, motorized infantry, mechanized infantry, airborne infantry, air assault infantry, and naval infantry. Other types of infantry, such as line infantry and mounted infantry, were once commonplace but fell out of favor in the 1800s with the invention of more accurate and powerful weapons.
A pike is a long thrusting spear formerly used in European warfare from the Late Middle Ages and most of the early modern period, and wielded by foot soldiers deployed in pike square formation, until it was largely replaced by bayonet-equipped muskets. The pike was particularly well known as the primary weapon of Swiss mercenary, German Landsknecht units and French sans-culottes. A similar weapon, the sarissa, had been used in antiquity by Alexander the Great's Macedonian phalanx infantry.
A schiltron is a compact body of troops forming a battle array, shield wall or phalanx. The term is most often associated with Scottish pike formations during the Wars of Scottish Independence in the late 13th and early 14th centuries.
The sarissa or sarisa was a long spear or pike about 5 to 7 meters in length. It was introduced by Philip II of Macedon and was used in his Macedonian phalanxes as a replacement for the earlier dory, which was considerably shorter. These longer spears improved the strength of the phalanx by extending the rows of overlapping weapons projecting towards the enemy. After the conquests of Alexander the Great, the sarissa was a mainstay during the Hellenistic era by the Hellenistic armies of the diadochi Greek successor states of Alexander's empire, as well as some of their rivals.
The phalanx was a rectangular mass military formation, usually composed entirely of heavy infantry armed with spears, pikes, sarissas, or similar pole weapons tightly packed together. The term is particularly used to describe the use of this formation in ancient Greek warfare, although the ancient Greek writers used it to also describe any massed infantry formation, regardless of its equipment. Arrian uses the term in his Array against the Alans when he refers to his legions. In Greek texts, the phalanx may be deployed for battle, on the march, or even camped, thus describing the mass of infantry or cavalry that would deploy in line during battle. They marched forward as one entity.
The pike square was a military tactical formation in which 10 rows of men in 10 columns wielded pikes. It was developed by the Swiss Confederacy during the 14th century for use by its infantry.
A shield wall is a military formation that was common in ancient and medieval warfare. There were many slight variations of this formation, but the common factor was soldiers standing shoulder to shoulder and holding their shields so that they would abut or overlap. Each soldier thus benefited from the protection of the shields of his neighbors and his own.
Line infantry was the type of infantry that formed the bulk of most European land armies from the mid-17th century to the mid-19th century. Maurice of Nassau and Gustavus Adolphus are generally regarded as its pioneers, while Turenne and Montecuccoli are closely associated with the post-1648 development of linear infantry tactics. For both battle and parade drill, it consisted of two to four ranks of foot soldiers drawn up side by side in rigid alignment, and thereby maximizing the effect of their firepower. By extension, the term came to be applied to the regular regiments "of the line" as opposed to light infantry, skirmishers, militia, support personnel, plus some other special categories of infantry not focused on heavy front line combat.
The army of the Kingdom of Macedon was among the greatest military forces of the ancient world. It was created and made formidable by King Philip II of Macedon; previously the army of Macedon had been of little account in the politics of the Greek world, and Macedonia had been regarded as a second-rate power.
A pitched battle or set-piece battle is a battle in which opposing forces each anticipate the setting of the battle, and each chooses to commit to it. Either side may have the option to disengage before the battle starts or shortly thereafter. A pitched battle is not a chance encounter such as a meeting engagement, or where one side is forced to fight at a time not of its choosing such as happens in a siege or an ambush. Pitched battles are usually carefully planned to maximize one's strengths against an opponent's weaknesses and use a full range of deceptions, feints, and other manoeuvres. They are also planned to take advantage of terrain favourable to one's force. Forces strong in cavalry, for example, will not select swamp, forest, or mountain terrain for the planned struggle. For example, Carthaginian General Hannibal selected relatively flat ground near the village of Cannae for his great confrontation with the Romans, not the rocky terrain of the high Apennines. Likewise, Zulu Commander Shaka avoided forested areas or swamps, in favour of rolling grassland, where the encircling horns of the Zulu Impi could manoeuvre to effect. Pitched battles continued to evolve throughout history as armies implemented new technology and tactics.
Infantry tactics are the combination of military concepts and methods used by infantry to achieve tactical objectives during combat. The role of the infantry on the battlefield is, typically, to close with and engage the enemy, and hold territorial objectives; infantry tactics are the means by which this is achieved. Infantry commonly makes up the largest proportion of an army's fighting strength, and consequently often suffers the heaviest casualties. Throughout history, infantrymen have sought to minimise their losses in both attack and defence through effective tactics.
The line formation is a standard tactical formation which was used in early modern warfare. It continued the phalanx formation or shield wall of infantry armed with polearms in use during antiquity and the Middle Ages.
Pike and shot was a historical infantry tactical formation that first appeared during the late 15th and early 16th centuries, and was used until the development of the bayonet in the late 17th century. This type of formation combined soldiers armed with pikes and soldiers armed with arquebuses and/or muskets. Other weapons such as swords, halberds, and crossbows were also sometimes implemented. The formation was initially developed by the Holy Roman Imperial (Landsknechte) and Spanish (Tercios) infantries, and later by the Dutch and Swedish armies in the 17th century.
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.
The Hellenistic armies is a term which refers to the various armies of the successor kingdoms to the Hellenistic period, emerging soon after the death of Alexander the Great in 323 BCE, when the Macedonian empire was split between his successors, known as the Diadochi.
Despite the rise of knightly cavalry in the 11th century, infantry played an important role throughout the Middle Ages on both the battlefield and in sieges. From the 14th century onwards, it has been argued that there was a rise in the prominence of infantry forces, sometimes referred to as an "infantry revolution", but this view is strongly contested by some military historians.
The ordre serré and the ordre profond were two ways of grouping soldiers.
Although the term infantry dates from the 15th century, the foot troops of the previous eras in history who fought with a variety of weapons before the introduction of the firearms are also referred to as infantry. During the Ancient and Middle Ages infantry were often categorized by the types of weapons and armour they used, such as heavy infantry and light infantry. Generally, light infantry acted as skirmishers, scouts, and as a screening force for the more heavily armed and armored heavy infantry, the latter of which often made up the bulk of many historic armies.
Roman infantry tactics are the theoretical and historical deployment, formation, and manoeuvres of the Roman infantry from the start of the Roman Republic to the fall of the Western Roman Empire. The focus below is primarily on Roman tactics: the "how" of their approach to battle, and how it stacked up against a variety of opponents over time. It does not attempt detailed coverage of things like army structure or equipment. Various battles are summarized to illustrate Roman methods with links to detailed articles on individual encounters.
The Macedonian phalanx was an infantry formation developed by Philip II from the classical Greek phalanx, of which the main innovation was the use of the sarissa, a 6-metre pike. It was famously commanded by Philip's son Alexander the Great during his conquest of the Achaemenid Empire between 334 and 323 BC. The Macedonian phalanx model then spread throughout the Hellenistic world, where it became the standard battle formation for pitched battles. During the Macedonian Wars against the Roman Republic, the phalanx appeared obsolete against the more manoeuvrable Roman legions.
