Combined Arms Manoeuvre

Records from the earliest empires show soldiers with standardised military equipment and the training and discipline required for battlefield formations and manoeuvres. These regular forces were kept small because of training and upkeep costs, and were supplemented by short-term mass-conscript irregular infantry. This established the core distinction between professional and levied foot troops that persisted almost to modern times.

Before the chariot created the first mobile fighting forces, all armies consisted solely of infantry. Even afterwards, with rare exceptions such as the Mongol Empire, infantry remained the largest component of most armies in history.

Egyptian records of the Battle of Kadesh give the first known organisation of military forces into regular units, with soldiers grouped into fifties, then 250s, 1,000s and finally commands of up to 5,000. Similar roughly decimal hierarchies appear in other ancient armies, prefiguring modern squads, companies and regiments.

From Classical Antiquity through the Middle Ages, infantry in the Western world were categorised as either heavy or light. This division shaped tactical organisation for over two millennia and was repeatedly reinvented as weapons changed.

Citizen soldiers armed with spear and shield fought shoulder to shoulder in a tight formation that depended on collective discipline rather than individual heroics, a model that shaped infantry tactics across the ancient Mediterranean world.

Gaius Marius opened legion service to citizens without property, standardised equipment and training, and made soldiering a long-term profession rather than a temporary levy, establishing the disciplined standing infantry force Rome relied on for centuries.

With the fall of Rome the quality of heavy infantry deteriorated and warfare came to be dominated by heavy cavalry such as knights, used as small elite shock units. Infantry were reduced to peasant militias and light troops drawn from the lower classes.

Technological development allowed large numbers of light infantry to be armed with ranged weapons without the years of training required for archers and slingers, beginning with crossbowmen, then hand cannoneers and arquebusiers. Rising firearm effectiveness marked the start of early modern warfare and eventually rendered heavy infantry obsolete.

Towards the end of the Middle Ages more professional and better trained light infantry demonstrated effectiveness against mounted knights. This began the reversal of cavalry dominance and the return of infantry to a central battlefield role.

By the start of the Renaissance infantry returned to a larger role, with Swiss and German formations using dense blocks of pikes to drive off cavalry. This re-established foot soldiers as the decisive arm of European armies.

The word infantry entered English around this time to describe soldiers who march and fight on foot. The individual-soldier term infantryman was not coined until 1837.

The bayonet allowed musket-armed infantry to defend themselves against cavalry without separate pikemen, so the infantry square replaced the pike square. This unified the infantry into a single firearm-equipped type.

Musketeer infantry were trained to fight in wide lines facing the enemy, filling the central battlefield role once held by heavy infantry but with ranged rather than melee weapons. Smaller dispersed skirmishing formations were created alongside them as light infantry, distinguished by tactics rather than lighter arms.

Reforms to formation depth, volley fire and integration with cavalry and light artillery made Swedish infantry the most tactically advanced in Europe, a model widely copied during and after the Thirty Years' War.

From the mid-18th century until 1881 British infantry were named as numbered regiments 'of Foot' to distinguish them from cavalry and dragoon regiments. The naming convention was abandoned in 1881.

Facing invasion, revolutionary France declared the entire able-bodied male population liable for military service, creating the model of the large, national, citizen-based infantry army that most modern armed forces still follow.

As enemy infantry firearms grew steadily more effective, cavalry increasingly spent their time in combat on foot. Line infantry and mounted infantry likewise fell out of favour in the 19th century with the invention of more accurate and powerful weapons.

Rising firepower diminished the use of infantry lines until all infantry became light infantry in practice, with riflemen operating as an element of combined arms. Armoured fighting vehicles replaced cavalry horses and airpower added a new dimension, but infantry remained pivotal to combined arms operations.

Continued increases to conscript soldiers' monthly pay, part of a multi-year plan, aimed to ease morale and retention pressures as a falling birth rate steadily reduced the number of young men available for compulsory service.

Reconnaissance and strike drone crews were formally built into infantry platoon and company structures rather than attached from specialist units, reflecting how central small uncrewed aircraft had become to how infantry fought and survived on the modern front.

Newly mobilised soldiers with limited training continued to be committed in small, dispersed groups against fortified Ukrainian positions, a tactic that traded heavy losses for slow, incremental territorial gains rather than large manoeuvre operations.

The Next Generation Squad Weapon programme continued equipping infantry and other close combat formations with the XM7 rifle and XM250 automatic rifle, chambered in a new 6.8mm cartridge intended to defeat body armour at longer range.

Facing continued criticism that short four-year terms left infantry units short of experience, the government examined raising the share of Agniveer recruits retained for full careers, after border tensions renewed debate about readiness.

Regular soldier numbers dropped to their lowest level in well over a century, short of the government's stated target, prompting a new recruitment contract and campaign intended to reverse years of declining applications and rising outflow.

Continued call-ups of reservists for operations in Gaza and along other fronts strained employers and families, while a political fight over drafting ultra-Orthodox men, following a Supreme Court ruling, threatened to fracture the governing coalition.

The first cohorts to complete a full year of compulsory service, up from four months previously, moved into reserve status, prompting reviews of training quality and equipment shortages identified during the longer call-up.

The Wehrdienst scheme asks 18-year-olds to complete a questionnaire on their willingness to serve and offers stronger pay and training incentives to volunteers, with a route back to compulsory service written into law if recruitment targets are missed.

Troops sent to help Russia repel Ukraine's incursion into the Kursk region suffered heavy early losses when committed in unfamiliar open terrain against drones and artillery, prompting reported changes in how following units were employed.

The call-up of some 300,000 reservists to reinforce infantry units in Ukraine marked the first mass mobilisation by a major power in decades, exposing severe shortfalls in training, equipment and non-commissioned leadership across the new formations.

Field Manual 3-24 codified lessons from Iraq and Afghanistan around protecting the population and small-unit initiative, reshaping infantry training and doctrine across Western militaries for the following decade of counter-insurgency campaigns.

Soviet motor rifle troops, built around armoured vehicles and roads, struggled against lightly equipped mujahideen fighting in difficult terrain, a lesson later relearned by other conventional armies fighting irregular forces in similar ground.

Allied infantry divisions landed across five beaches against prepared German defences, opening the Western Front and demonstrating the scale of coordinated infantry, naval and air planning an amphibious assault demanded.

Specially trained storm troops bypassed strongpoints to attack weaker points and disrupt rear areas, a doctrine that influenced infantry small-unit tactics for the rest of the century after trench deadlock had made frontal attack prohibitively costly.

Combined with barbed wire and trench systems, sustained automatic fire halted massed infantry attacks within the war's opening months, forcing armies to develop new tactics, weapons and eventually tanks to restore mobility to the battlefield.

Classifications of infantry multiplied to reflect modern equipment and tactics, including motorised, mechanised or armoured, mountain, marine and airborne infantry. The subspecialties allowed foot soldiers to be delivered to and sustained in a wide range of operational environments.