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Infantry

The First World War precipitated a revolution in infantry tactics that changed the course of warfare. Armies adapted to modern industrialized war along a four-year learning curve, moving from 19th century linear formations to trench warfare and ultimately to mobile combined arms.

Introduction

Foot soldiers represented every army’s basic offensive arm in 1914. Their pre-war training focused primarily on marksmanship, the bayonet and discipline. Pre-war infantry tactics emphasized successive attack waves using speed and ferocity to achieve battlefield objectives. Modern industrial weaponry such as breech-loading artillery, machine guns and bolt-action rifles granted tremendous advantages to the defender during the First World War. Furthermore, most armies employed an elastic defense by 1917. This defense-in-depth tactic, introduced by the Imperial German Army in late 1916, involved defenders allowing attackers to capture lightly manned forward trenches so they could decimate them with machine gun fire and counterattacks from well-fortified rear trenches. Attackers grappled with the tactical challenges of surviving “no man’s land,” dislodging an entrenched enemy, and restoring mobility to the battlefield. The rigid mass infantry assault tactics from the previous century resulted in heavy losses against superior defensive firepower in 1914. Unable to move forward, armies entrenched by 1915 and developed trench warfare tactics for the purpose of advancing from one trench to the next in the face of intense firepower. These tactics resulted in only modest territorial gains in 1915 and 1916. By the last two years of the war, however, most tactical doctrines featured more sophisticated infantry techniques for breaking the trench warfare stalemate, such as flexible formations, fire-and-maneuver and infiltration. Eventually, armies integrated advanced weapons and combined arms into these new offensive tactics.

Flexible Formations

By 1917, all armies were replacing ridged mass infantry attack formations with smaller, more flexible columns and skirmish lines for the purposes of maneuverability and safety from enemy fire. Lieutenant General Ivor Maxse (1862-1958) made flexible formations a permanent feature of British Army infantry doctrine when he became Inspector General of Training in 1918. Maxse advocated for platoons to advance in columns with five to six yards between each soldier. United States Army tactical publications prescribed small, flexible, single or double file infantry columns instead of long rigid lines when traversing ground under enemy fire in 1918.

Fire-and-Maneuver

Opposing artillery, machine guns and barbed wire made it necessary to support offensive infantry maneuvers with firepower. Fire-and-maneuver involved one group of soldiers directing fire against an enemy position while another group maneuvered to converge upon that position from the flank or rear. The fire element suppressed the defenders as the maneuver element attacked and neutralized them. Early in the war, Imperial German Army infantry assault teams took turns firing and advancing. One group of soldiers drew enemy fire while the other moved forward. By 1917, the French Army called for attackers to support one another with suppressing fire as they moved from cover to cover until they were near enough to engage the enemy in close combat.

Infiltration

Armies started experimenting with infiltration tactics in 1915. The purpose of infiltration was for infantry to take advantage of the successes of an attack and sidestep the failures. Exploiting breaches as rapidly as possible overwhelmed defenders and prevented them from regrouping and counterattacking. Major Wilhelm Rohr (1877-1930) pioneered infiltration tactics in the Imperial German Army in 1916 and 1917. Mobile infantry units broke through weak points in enemy lines, attack units exploited these gaps, and fortification units consolidated gains. The Imperial German Army used these “storm trooper” tactics to advance up to forty miles in just a few days during the Spring Offensives in 1918. By 1917, French infantry assault tactics called for platoons to advance in surges. The first surge neutralized enemy defensive positions and machine guns. The second surge penetrated enemy lines and captured ground. The third surge consolidated territorial gains. United States Army infantry doctrine described the first assault surge circumventing enemy strong points and leaving them for subsequent attack surges. The first surge held captured ground until reinforcements arrived. The second assault surge avoided stacking behind units that were stalled by enemy resistance and passed through breaches in the enemy line.

Advanced Weapons and Combined Arms

Four years of trial and error on the battlefield led the armies of the First World War to fuse new offensive infantry tactics with advanced weapons in their attempts to break through and exploit strong defenses. The Imperial German Army armed its assault teams with grenades, portable machine guns and flamethrowers by 1916. United States Army tactical doctrine combined automatic rifles, grenades and mortars with fire-and-maneuver. American automatic riflemen suppressed enemy strong points while attackers used grenades and stokes mortars as they outflanked them. Infantry eventually became part of an increasingly sophisticated combined arms scheme that included artillery, tanks and aircraft. The Imperial German Army introduced the creeping barrage in 1916. A creeping barrage involved the infantry advancing behind a protective curtain of artillery fire. Over 300 tanks supported the British Army’s minor breakthrough at Cambrai in 1917. French Army doctrine in 1917 described aircraft providing support for the infantry by observing, strafing and bombing enemy targets on the ground. By the end of the First World War, infantry tactics had moved far beyond the 19th century and began to reflect those of the Second World War.

Jeffrey LaMonica, Delaware County Community College

Section Editor: Mark E. Grotelueschen
Jeffrey LaMonica: Infantry, in: 1914-1918-online. International Encyclopedia of the First World War, ed. by Ute Daniel, Peter Gatrell, Oliver Janz, Heather Jones, Jennifer Keene, Alan Kramer, and Bill Nasson, issued by Freie Universität Berlin, Berlin 2015-11-20. DOI: 10.15463/ie1418.10773
Note

Images6

German Storm troops
A German assault squad/Storm Troops (Stosstrupp) lie armed to attack enemy positions.
Unknown photographer: Belgien, Flandern, Sturmtrupp, black-and-white photograph, Flanders, Belgium, n.d.; source: Bundesarchiv, Bild 146-2008-0086, via Wikimedia Commons http://commons.wikimedia.org/wiki/File:Bundesarchiv_Bild_146-2008-0086,_Belgien,_Flandern,_Sturmtrupp.jpg.
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Germany license: http://creativecommons.org/licenses/by-sa/3.0/de/deed.en.

American troops with Vickers machine guns
The machine gun was invented in 1884, but armies were slow in adopting it until the invention of high-velocity, smokeless cartridges made it simultaneously more deadly and more concealable. Successful employment of machine guns by both sides in the Russo-Japanese War of 1904-1905 hastened its procurement throughout Europe. The USA remained largely aloof from these developments and, after going to war in 1917, were obliged to rely chiefly upon British and French designs to equip its machine gunners.
Unknown photographer: American Machine Gun Crews in the Great War, black-and-white photograph, n.p., n.d., in: Canfield, Harry S.: The World War: A Pictorial History, New York, 1919; source: HathiTrust Digital Library, http://hdl.handle.net/2027/uiug.30112054777732; contributed by Eric Brose.
This image has been identified as public domain.

German soldiers cleaning their rifles
Rifle cleaning was a typical exercise in the daily life of a soldier. Pictured are German soldiers cleaning their rifles in a trench. This routine activity did not only preserve the proper functioning of the rifles; it also familiarized the soldiers with the handling of them.
Unknown photographer, black-and-white photograph, n.p., n.d.; source: Bayerisches Armeemuseum, Fotoalbum, Inv. Nr. 314-88.
Contributed by Dieter Storz.

Guarding a subway entrance in Paris, 1914/15
French infantrymen guard a subway entrance in Paris during the early stages of war. At this point they are still wearing soft caps, red trousers and carrying bolt-action rifles with bayonets. In the latter stages of the war, soldiers would have been equipped with steel helmets, horizon blue uniforms, and a variety of advanced weapons, including automatic rifles, rifle grenade launchers, and hand grenades.
Bain News Service: Guarding subway entrance, black-and-white photograph, Paris, ca. 1914/15; source: Library of Congress Prints and Photographs Division, LC-DIG-ggbain-17036, http://www.loc.gov/pictures/item/ggb2005017236/.
Courtesy of the Library of Congress.

French troops on the Alsace-Lorraine Front, 1915
French troops man an advanced trench on the Alsace-Lorraine Front, 1915.
Section Photographique de l’Armée photographer, January 1915, Lorraine, France.
IWM (Q 53620), http://www.iwm.org.uk/collections/item/object/205024564.

In the trenches of Champagne
French soldiers photographed in the first line of trenches at the First Battle of Champagne.
Agence Rol: Tranchée de 1ère ligne en Champagne, black-and-white photograph, 1915; source: Gallica, Bibliothèque nationale de France, Rol 45762, http://gallica.bnf.fr/ark:/12148/btv1b6909089d.
This image has been identified as public domain.