Armies and Infantry: Modern Summary

  • Last updated on November 11, 2022

Modern infantry warfare began in the sixteenth century with the advent of the pike, which transformed the concept of the infantry.

Nature and Use

Modern infantry warfare began in the sixteenth century with the advent of the Pikespike, which transformed the concept of the infantry. The pike was utterly useless when used alone, but when used together with hundreds of other pikes, it was harder to stop and harder to attack than was any other hand weapon. However, for thousands of pikemen to work together, they had to learn to march in time to the beat of the drum, and they had to learn to respond simultaneously and uniformly to a series of clearly understood commands. The effectiveness of the pike was utterly dependent on order, and disorder spelled disaster. The solution was Drills (marching exercises)drill, or marching exercises.Armies;modernInfantry;modernArmies;modernInfantry;modern

The Pikemen;SwissSwiss, who revolutionized the employment of the pike, and were quickly copied by every other nation in Europe, had developed a system of drill that allowed for rapid movement in good order, instant changes of facing, wheeling, opening, and closing of the intervals between ranks and files and the merging of ranks and files. They had also developed a series of standard motions for individual pikemen, so that when the command was given to “Port your pike,” all pikemen knew exactly what posture to assume.

Although the Swiss did not invent drill, they created a degree of emphasis and elaboration that had not been seen since the days of the Roman legions. In the sixteenth century, if one wanted to be an effective pikeman, one had to learn and practice, and then continue to practice. Every man, from front to rear, had to be a professional. Amateur militia could and did attempt to master the drill and weapons of the professionals, but they were nearly always swept aside if they got in the way of professional pikemen.

In the sixteenth century, the word “professional” was generally synonymous with Mercenaries;synonymous with “professional”[professional]Professional militaries;and mercenaries[mercenaries]“mercenary,” and the armies of sixteenth century Europe were composed of mercenaries from all over Christendom. Because these mercenaries required payment, failure to pay could result in strikes, mutinies, desertions, or even outright betrayal. It could even lead to disasters such as the Sack of Rome, Sack of (1527)Rome in 1527, in which an imperial army stormed and brutally pillaged the Holy City, even though the emperor had made peace with the pope. In another disaster, known as the Spanish Fury Spanish Fury (1576)(1576), an unpaid Spanish army that had been sent to the Netherlands to crush a revolution rekindled it by sacking the pacified city of Antwerp.

The pike alone was inadequate for battle; pikemen were at a serious disadvantage against missile weapons. At Bicocca Bicocca, Battle of (1522)(1522), an unsupported Swiss pike formation was shot to pieces by Spanish and imperial harquebusiers after they were stalled behind a sunken road. These same harquebusiers gave a similar treatment to the French cavalry at Pavia Pavia, Battle of (1525)(1525) when they hid behind hedges to blast the armored knights from their horses.

The successes of the Harquebusiersharquebusiers, ironically, highlighted their weakness: They were able to bring their full power to bear only when they had an obstacle between them and their targets, which kept their enemies just out of reach. Essentially, the Shot (firearm infantry, generic term for)“shot,” a generic term for firearm troops, was strong where pikes were weak, and pikes were strong where the shot was weak. When combined, the pikes could defend the shot from cavalry and other pikes, while the shot could kill from a distance. When combined, these forces were formidable.

Despite its flaws, the Firearms;and pikes[pikes]firearm killed as had no weapon that previously had been seen on any battlefield. It smashed through armor, it crushed bone, and it tore through soft tissue. It had what modern soldiers call “lethality,” and it behooved sixteenth century commanders to develop tactical systems that optimized its strengths and mitigated its weaknesses. Part of this strategy was combining firearms with pikes, the other was developing a firing drill as elaborate as those of the pikes.

The most common method was to arrange the shot in a formation of eight to twelve ranks. The first rank would fire and fall away to the rear of the formation to reload. The next rank would then step up and fire, followed by the next, followed by the next. The commander could time his shots to regulate the expenditure of ammunition or intensify his fire as needed. An eight-rank formation could sustain a rate of fire of one volley every five seconds. These formations could advance or retire while firing and deliver aggressive, point-blank attacks at a jog or run. They could also double their ranks to the front, thus turning eight ranks into four, and deliver a single smashing volley in the face of an enemy charge.

This formidable combination of firepower and shock effect made infantry the anchor of any battle formation. Ironically, however, the infantry’s limited mobility meant that it was not usually the decisive force in battle. A common scenario would be for the infantry to plod ahead and lock its opposite numbers in prolonged “push of pike” and point-blank musketry, while the cavalry battled on the flanks. The Cavalry;position in battlecavalry that was victorious would then ride around the rear of the enemy infantry. Most infantry would break and run at this point, while the best soldiers, such as the Spanish tercios at RocroiRocroi, Battle of (1643)(1643), would form squares and patiently wait to die.


For most of the sixteenth century, pikes favored extremely deep formations of as much as a hundred ranks depth. At the core of these formations would be the colors and the “double-pay men,” who would issue forth through the intervals between the files to smash a stubborn enemy with halberds or two-handed swords. The shot, in massive formations, would form blocks on the wings. The advantage of such formations, often called “battles,” were their tremendous staying power; there was always someone to take the place of the man who fell. Such formations could also form a 360-degree defense in seconds by facing every man to the outside. They could also provide a place of relative safety in the rear ranks, where new recruits could be seasoned. They almost certainly provided a huge morale boost, assuring each soldier that he was part of something massive and invincible. They were, however, also tremendously wasteful of manpower. The Dutch commander Maurice of Maurice of NassauMaurice of NassauNassau (1567-1625) had to make much more frugal use of limited resources in his rebellion against the Spanish, so he developed a system where the “battles” were reduced to “battalions” of twelve ranks depth in the pikes and eight in the shot.

The battalion Battalion (army unit)formation, with pikes in the center and shot on the flanks, allowed every man to use his weapon, and provided for much greater tactical flexibility. Conversely, it meant that every man needed to pull his weight, and that there was no “safe” place to keep the less reliable men.

Infantry Around the World

The firearm spread rapidly and was adopted from Japan to Morocco. The Japan;infantryJapanese, under the influence of the Portuguese, developed a balanced infantry force that combined harquebuses with blocks of well-drilled spearmen.

Outside Japan and western Europe, the adoption of the firearm did not bring with it a parallel adoption of pikes, a development of drill, or an improvement in the status of the infantry. In India’s Mughal Empire, Persia, and Muscovy, infantry remained at best old-fashioned and at worst rabble. The Cavalry;status vs. infantrycavalry was the place of honor and the key to victory. In China;infantryChina it was said that one should not use good iron to make a nail, nor a good man to make a soldier, emphasizing long-term strategy over tactical efficiency.

Only in the Ottoman Ottoman Empire;infantryEmpire was there a large and efficient corps of professional infantry, known as the Janissariesjanissaries. They were armed primarily with firearms and relied on friendly cavalry and wagons to protect them from enemy cavalry. Unlike European shot, they were freely engaged in close combat and carried both swords and shields. They would deliver a close-range blast at their enemies, draw their swords, and charge. They did not employ rigid formations or precise drill. Although the Turkish janissaries were the best in the world in the fifteenth century, they generally found themselves outclassed by pike and shot formations on level ground in the sixteenth.

Interestingly, while Europe continued to develop increasingly more deadly and efficient ways of making war, the armies of the East changed little until they found themselves the objects of European imperial ambitions in the eighteenth and nineteenth centuries. They then either adapted to a European model or were conquered.

The Age of the Bayonet

The Bayonetsinvention of the socket bayonet at the end of the seventeenth century combined with several ongoing developments to reinvent warfare for the eighteenth century. The socket Socket bayonetsbayonet, meant that a soldier could both shoot a musket and defend himself. When formed shoulder-to-shoulder, a row of bayonets did as well as a row of pikes at warding off a cavalry attack, but this same impenetrable wall of steel points could also deliver a deadly hail of lead. At the end of the seventeenth century, the shot had dominated the field, with a small contingent of pikes waiting only to chase off cavalry. With the advent of the bayonet, the pike was instantly discarded.

The simultaneous adoption of the Flintlocksflintlock and the later introduction of the steel Ramrodsramrod also served to increase the soldier’s rate of fire from one to two or even three to four shots a minute. Warfare became a process of massing one’s firepower in the decisive point, delivering an effective volley, and charging home with the bayonet. With high rates of fire and universal use of muskets, formations quickly went from the eight ranks of the Dutch system to four, to three, and then to two ranks.

Drill Drills (marching exercises)also changed. The focus became one of making the soldier a nonthinking cog in a machine whose purpose was to march in a steady and orderly manner, close within a few yards of an enemy, deliver an orderly and smashing volley, and charge home with the bayonet–or to stand its ground against an enemy trying such an attack. Drill took on the jerky, precise, and rapid form now associated with drill teams, and soldiers were, for the first time, forced to stand absolutely still when at “attention.” In fighting the natural tendency to fidget and look around, the soldier was distracted from the natural tendency to flinch and to feel fear.

In the eighteenth century, these well-drilled lines of infantry dominated military operations. Cavalry could still deliver a decisive blow, and artillery was getting more mobile and more deadly, but most battles were being settled by steadiness, discipline, and the effective use of infantry firepower.

The French Revolutionary Wars French Revolution (1793-1793)(1792-1802) and the Napoleonic Wars Napoleonic Wars (1793-1815)(1803-1815) saw one major change in the idea of infantry effectiveness. The French revolutionary armies could not match the royal armies of Europe in drill and precision, but they could outmatch them in numbers and motivation. Although the infantry of France still learned to march in step and fire on command, their favored formations–attack columns with loosely formed “light infantry” screens–were designed to complement the idea of massing overwhelming force at the decisive point and using that force aggressively.

The Industrial Age

Following the Napoleonic Wars, infantry formations became more loose, and drill became less rigid. Attacks became less about marching mechanically into the face of the foe, and more about enthusiastic bayonet charges, supported by massed artillery. The nineteenth century conscript and reservist armies had to be more motivated by nationalism and belief in a cause than by drill and iron discipline.

The introduction of the Breech-loading weapons[Breech loading weapons];riflesRiflesbreech-loading rifle accelerated this development when it doubled the infantryman’s rate of fire, and made him capable of firing just as well, if not better, from the prone position as he did standing. The infantry line was reduced from two ranks to one, and commanders emphasized spirit and speed in the attack and rapid, accurate fire in the defense.

As formations became more loose, and men tended to seek cover, officers became concerned about losing control of men whom they could not see and who could not see them. They worried about soldiers panicking and wasting ammunition in blind firing or finding a hole and staying there.

During World War World War I (1914-1918)[World War 01];infantryI, infantry operated in even looser formations than had been seen previously, but the Napoleonic notion of success based upon massed force and will to win remained strong. The futility of human wave assaults is well known, but it should be mentioned that if these attacks had always failed–if the combination of machine guns, barbed wire, artillery, and rifle fire had stopped the infantry dead, then they would not have been employed as they were for so long. The fatal problem was that these bayonet attacks did work or at least achieved limited success a fair amount of the time.

While casualties increased at Verdun (1916), the Somme (1916), and Vimy Ridge (1917), there were developments taking place that would point the way toward the future of the infantry. The French were developing a system for small-unit operations that involved some units providing covering fire, while others maneuvered to new firing positions, whence they would provide covering fire in their turn. They had perfected the “fire and maneuver” Fire and maneuver systemsystem that is the key to all modern small-unit infantry tactics.

The Germans formed elite corps of heavily armed and well-trained shock troops called Sturmtruppen, or storm Storm troopers troopers, who would slip forward and probe for weaknesses in the line. When they found one, they would attack with grenades and other close combat weapons to punch a hole in the enemy’s trench lines. While the main body of the infantry widened the holes and eliminated strongpoints, teams of storm troopers would work their way deep into enemy territory, disrupting communications, ambushing reinforcements, and attacking supply and command centers.

The most significant development for the infantryman in World War I was not tactical but technological. The British solution to the trench warfare problem was the Tankstank. The massive iron war machines of World War I were crude in nature, but by World War II, they had come to be the decisive force on the battlefield.

In World War World War II (1939-1945)[World War 02];infantryII, infantry without tanks were no better off than had been the infantry in the trenches of World War I. However, if tanks without infantry encountered enemy infantry, they had to “button up” and blindly crash around until immobilized and killed by infantrymen they could not see. Therefore, by the twentieth century, tanks and infantry had developed a symbiotic relationship similar to that of the sixteenth century pikes and shot. Each needed the other to survive and win.

The twentieth century infantryman became a member of a combined arms team that balanced the strengths and weaknesses of foot soldiers, tanks, artillery, and to an increasing degree, aircraft. He also became accustomed to operating more autonomously than ever before. The modern battlefield is an alarmingly empty place. Friends and foes alike are concealed, and all are disbursed. The infantryman can see only a few friends and can usually glimpse the enemy for only a few fleeting moments. Modern infantrymen must be able to work in small and often unconnected groups toward a common goal. Soldiers are made to understand the plan and their place in it and should be willing to continue to carry out the mission even when out of the sight of leaders. Many infantries have not met this standard, and large numbers of soldiers in any operation spend the whole time isolated and paralyzed by uncertainty, but success in modern combat depends on some significant number of soldiers continuing to carry on, despite uncertainty.

U.S. soldiers from the 289th Infantry make their way down a snowy road in Belgium in January, 1945.

(National Archives)

In World War II, infantrymen who had been assigned to tank formations frequently rode in armored personnel carriers that provided enough mobility to keep up with the tanks, as well as some protection. The armored personnelArmored personnel carrierscarrier evolved into the tanklike armored fighting Armored fighting vehiclesvehicle (AFV), and the modern mechanized infantry commander is constantly faced with the decision of when or if to dismount his infantry. If they are dismounted too soon, they get left behind or slow down the advance; if they are dismounted too late, the tanks may be destroyed by enemy antitank weapons, incinerating the infantry in their vehicles.

At the end of the twentieth century, infantry remained central to operations in Vietnam and Korea, and in counterinsurgency operations in Northern Ireland. In large-scale, conventional wars such as the Gulf War Gulf War (1990-1991);infantry(1990-1991), however, infantry was primarily defined by its relationship to the armored vehicle. In modern U.S. Army parlance, an infantry-man, on foot, doing what an infantryman has always done, is called a Dismount (infantryman)“dismount,” as if to suggest that his natural place is inside an armored vehicle, and his existence as an infantryman is a temporary and transitory state of affairs.Armies;modernInfantry;modern

Books and Articles
  • Addington, Larry H. The Patterns of War Since the Eighteenth Century. 2d ed. Bloomington: Indiana University Press, 1994.
  • Army Historical Foundation. U.S. Army: A Complete History. Arlington, Va.: Hugh Lauter Levin Associates, 2004.
  • Carver, Michael. Britain’s Army in the Twentieth Century. London: Macmillan, 1998.
  • Duffy, Christopher. The Military Experience in the Age of Reason, 1715-1789. New York: Barnes and Noble Books, 1987.
  • English, John A. Marching Through Chaos: The Descent of Armies in Theory and Practice. Westport, Conn.: Praeger, 1996.
  • English, John A., and Bruce I. Gudmundsson. On Infantry. Westport, Conn.: Praeger, 1994.
  • Griffith, Paddy. Battle Tactics on the Western Front: The British Army’s Art of Attack, 1916-1918. New Haven, Conn.: Yale University Press, 1994.
  • House, Jonathan M. Combined Arms Warfare in the Twentieth Century. Maps by George Skoch. Lawrence: University Press of Kansas, 2001.
  • Keegan, John. The Face of Battle. New York: Barnes and Noble Books, 1989.
  • Killingray, David, and David Omissi, eds. Guardians of Empire: The Armed Forces of the Colonial Powers, c. 1700-1964. Manchester, England: Manchester University Press, 1999.
  • Mackenzie, S. P. Revolutionary Armies in the Modern Era: A Revisionist Approach. New York: Routledge, 1997.
  • Marshall, S. L. A. Men Against Fire: The Problem of Battle Command in Future War. New York: William Morrow, 1947.
  • Oman, Sir Charles. A History of the Art of War in the Sixteenth Century. 1937. Reprint. Mechanicsburg, Pa.: Stackpole Books, 1999.
  • Osgood, Richard. The Unknown Warrior: An Archaeology of the Common Soldier. Stroud, Gloucestershire, England: Sutton, 2005.
  • Ross, Steven T. From Flintlock to Rifle: Infantry Tactics, 1740-1866. Rutherford, N.J.: Fairleigh Dickinson University Press, 1979. Reprint. Portland, Oreg.: F. Cass, 1996.
  • Smith, Digby George. Armies of 1812: The Grand Armée and the Armies of Austria, Prussia, Russia, and Turkey. Staplehurst, England: Spellmount, 2002.
  • Tsouras, Peter G. Changing Orders: The Evolution of the World’s Armies, 1945 to the Present. New York: Facts On File, 1994.
Films and Other Media
  • Band of Brothers. Television miniseries. Home Box Office, 2001.
  • The Big Red One. Feature film. Lorimar, 1980.
  • Kelly’s Heroes. Feature film. Avala Film, 1970.
  • Weapons at War: Infantry. Documentary. History Channel, 1999.

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Categories: History