♦ The Infantry Regiment 1941-45 ♦

The United States Army in World War II


US infantry of the Japanese-American 442nd Regimental Combat Team moving up, Europe, 1944. (US Army Center of Military History)

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The US Army’s World War II infantry division was built around three infantry regiments. From the Civil War to the Great War the regiment was the Army’s largest permanent formation, and those of the Infantry branch were the most numerous. The National Defense Act of 1916 and World War I integrated the National Guard and the National Army (later the Organized Reserve) with the Regular Army into a single regimental system with a common regimental organization.

The experience that it acquired on World War I battlefields greatly influenced the Army’s thinking about the configuration and tactical employment of the infantry regiment. The old idea that the individual infantryman, armed with rifle and bayonet, was the infantry regiment’s primary “weapons system” was not, indeed, discarded. But trench warfare had revolutionized small-unit infantry tactics, replacing direct shock action with fire and maneuver. The German Army had shown the way forward with its employment of specially trained assault units (Stosstruppen): infantry battalions incorporating an array of support weapons such as light machine guns, mortars and flamethrowers. The governing principle was unity (Einheit): that units at every level should embody all the resources required to carry out their assigned tasks.

In the German Army’s 1918 Mob-Division, each infantry battalion had a platoon of light trench mortars and a machine gun company in addition to its four rifle companies. At the regimental level were found additional support weapons: flamethrowers, heavy trench mortars, light artillery. When Germany began to rearm in the mid-1930s, a similar organization was adopted. The German infantry regiment had a cannon company and an antitank gun company, while its battalions included a heavy company with machine guns and mortars.

The US Army infantry regiment as reorganized in the 1930s followed the German Einheit principle. At the regimental level there was a cannon company and an antitank gun company. At the battalion level there was a heavy weapons company with medium mortars and machine guns; the rifle company included a weapons platoon with light mortars and machine guns. Thus commanders at every level had available to them an array of supporting weapons. The commander of a rifle company, for instance, could support his rifle platoons with the fires of a machine gun squad and a 60mm mortar squad.

The basic building block of the rifle platoon, rifle company, infantry battalion and ultimately the infantry regiment was the rifle squad. In 1943-45 it consisted of twelve men: two noncommissioned officers and ten lower enlisted. The squad leader was usually a staff sergeant; the assistant squad leader could be a sergeant or a corporal. All personnel except the automatic rifleman were armed with the M1 semiautomatic rifle. The automatic rifleman was armed with the M1918A2 Browning Automatic Rifle. Three of the M1 riflemen also had an M7 rifle grenade launcher. Each platoon had one M1908 Springfield sniper rifle; this was issued to an expert marksman in one of the squads in place of his M1.

US Army infantrymen, northwest Europe, 1945-45. (US Army Center of Military History)

Squad organization for combat was as follows: scout team (squad leader and two riflemen, one grenade launcher); BAR team (automatic rifleman and four riflemen); rifle team (assistant squad leader and four riflemen, two grenade launchers). Tactical doctrine on the attack was for the scout team to locate the enemy, the BAR team to establish a base of fire, and the rifle team to maneuver and close on the objective. Movement when contact was anticipated could also be be conducted by splitting the squad into two groups, with one covering the movement of the other in a series of bounds. On defense, the BAR team was sited to cover the most likely avenue of approach, with the rest of the squad positioned in support. All of these formations could be modified as circumstances might dictate.

As things turned out, however, the rifle squad was rarely employed as an independent unit. It proved too large to be controlled by the squad leader when split up into the three teams described above, especially in view of the chronic shortage of experienced NCOs.  Control, therefore, was exercised at the platoon level and the squads were not divided up. Platoon and company tactics were generally “triangular,” e.g. two elements up with one held back. When attacking, the third element would be the maneuver force, moving to a flank and conducting a close assault while the other two elements provided fire support. On defense it was customary for two elements to man the line with the third one in reserve, positioned to mount a counterattack in case of a breakthrough.

Organization of the infantry rifle squad as depicted in a WW II Army field manual (War Department publication)

At the regimental level, the cannon and antitank companies proved somewhat disappointing. Originally (1942) the former was equipped with 6 x 75mm guns and 2 x 105mm howitzers mounted on armored halftracks. But these self-propelled assault guns were soon replaced by 6 x towed M3 105mm light howitzers, a weapon originally developed for the airborne divisions. This change was in line with the desire to keep the infantry division as light as possible. Unfortunately the towed howitzers were insufficiently mobile and too vulnerable to be employed in close support of the infantry. Nor did the cannon company possess the fire direction capabilities necessary to deliver accurate indirect fire. Thus it was usually attached to the division artillery. The antitank company's towed M1 57mm antitank guns also lacked mobility, and at best they were marginally effective against the German tanks encountered in 1943-45. These deficiencies were noted in a review of the infantry division conducted by the General Board, European Theater of Operations, US Army, immediately after the termination of hostilities in June 1945.

The General Board's conclusions had been anticipated in the second half of the war when it became common practice to employ the infantry regiment in the form of a regimental combat team (RCT). The RCT was created by attaching various units to the infantry regiment, typically a 105mm field artillery battalion, a combat engineer company, a tank company or tank destroyer company, etc. The RCT thus bore a certain similarity to the German Army's Kampfgruppe (battle group) concept, i.e. task organization for combat. Some of the units used to augment the regiment were organic to the infantry division but others, particularly the tanks and tank destroyers, were not. The Board recommended that the future infantry division should include an organic tank battalion whose companies could be allotted to the regiments, and this recommendation was adopted in the postwar period.

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Organizational Diagrams



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