The estate of the late John Sayen has graciously given the Tactical Notebook permission to serialize his study of the organizational evolution of American infantry battalions. The author’s preface and the previous section of this book may be found via the following links:
Under the National Defense Act of 1920, the Regular Army was supposed to maintain twelve infantry divisions and three cavalry divisions. Nine of the infantry and all the cavalry divisions would be stateside forming the nucleus of nine “army corps.” The three remaining infantry divisions would reside permanently overseas in the Canal Zone, Hawaii, and the Philippines, respectively. Stateside, the 2nd Division would be maintained at wartime strength both as a rapid reaction force and to conduct experiments with the 1921 division structure. The infantry itself totaled 65 regiments (numbered 1 through 65) in 1920. These included the four provisional Philippine Scout regiments, originally organized in April 1918. From 1920, they became known as the 43rd, 45th, 57th, and 62nd Infantry and replaced previously disbanded non-Filipino wartime-only units that had carried the same numbers. Likewise, the old Puerto Rican regiment, which had existed without a number since 1908, became the new 65th Infantry.[1]
These 65 regiments constituted a very respectable force, indeed much more respectable than what either Congress or the public was willing to pay for. The belief that there would be no more major wars, the creeping realization of just how expensive the last war had really been, plus a wave of isolationist and antiwar sentiment all combined to persuade Congress to enact drastic cuts in the Army’s budget and authorized manpower. In late 1921, these cuts caused the Army to deactivate 18 infantry regiments. Eight more followed in 1922 and one in 1927. The Army’s actual end strength dropped from a peak of 230,000 (out of an authorized strength of 280,000) in 1921 to less than 149,000 in 1922. Falling again to 133,000 in 1923, it never rose above 143,000 until 1936. The War Department itself further weakened the infantry in order to strengthen other arms that it considered more important. For example, it sacrificed the freshly created Philippine Scout 43rd and 62nd Infantry in order to create cavalry, coast artillery, engineer and other support units. Five infantry battalions had to deactivate in 1930 to meet Air Corps manpower demands.
Between 1920 and 1932 the combined effect of all these cuts reduced the infantry branch by 63% or from 110,000 to a little over 40,000. Most of the 38 surviving infantry regiments could exist only at strengths well below what even the November 1920 peacetime tables prescribed. Even the Army’s elite war strength experimental and demonstration unit, the 29th Infantry was not immune. Stationed at Fort Benning, it had the only active howitzer company in the Continental United States (other regiments had no more than howitzer platoons) and was one of only two regiments to actually field a headquarters company rather than a headquarters detachment. However, even this much-favored regiment could field only two active battalions and the same was true of at least 13 other regiments. Many regiments could only maintain their battalions at enlisted strengths of 300 or 320 apiece. The overall enlisted strength of some regiments fell to 830 or less. The two battalions in the 15th Infantry in China, for example, had only two rifle companies and a half strength machinegun company apiece.
Other overseas regiments did better, however. For example, the 14th and 33rd Infantry in the Canal Zone were relatively strong at 1,724 enlisted each. The surviving Philippine Scout regiments (the 45th and the 57th) stayed fairly flush also. Regiments attached to Army schools used special organizations designed to fit the needs of those schools. However, even three-battalion regiments in the Continental United States rarely totaled more than 1,000 men. Of the nine Regular Army divisions in the Continental United States, only three (1st, 2nd, and 3rd) were even theoretically manned at their full peace establishments of just under 11,000 each. The 4th, 5th, and 6th Divisions retained only skeletal infantry regiments with most of their other elements inactivated. The 7th, 8th, and 9th divisions had no troops assigned to them at all and existed only on paper.
Overseas, the Hawaiian Division was generally complete but the Panama Canal Division amounted to little more than a brigade, and the Philippine Division lacked most of one infantry regiment and more than half its artillery. Reserve forces fared just as badly. The National Guard could not maintain more than half of the 435,000 men it was authorized. The military skills of the 100,000 officers in the Organized Reserves were becoming stale because there was no money for refresher training. Enlisted (non-National Guard) reservists hardly existed at all because no one had budgeted any money for recruiting them.[2]
Such stringent financial conditions certainly retarded but by no means halted the Army’s further progress in experimentation and reorganization. One of the earliest projects was to find a replacement for the unsatisfactory Stokes mortar and the 37mm gun of the howitzer company.
Initially, the Army designed a dual-purpose 2.24-inch (57mm) gun-howitzer. This weapon could fire a six-pound semi-armor piercing shell at low angle or lob a 10-pound high-explosive shell for high angle work. Testing showed that the six-pound shell lacked a sufficient bursting charge while the 10-pound shell was inaccurate and tumbled in flight. The biggest problem, however, was to design a carriage within a reasonable weight limit that would permit both low and high angle firing. After the gun burst during a firing trial, the Army abandoned its search for a dual-purpose weapon but continued to pursue single purpose weapons. It rolled out a prototype mortar in 1922 and a modernized 37mm gun in 1925.
Compared to its 1916 predecessor the 1925 37mm gun offered a better carriage and a longer barrel that allowed the use of more powerful ammunition but its weight rose to 360 pounds. The 1922 “mortar” was actually a small breech loaded howitzer with a rifled barrel, a wheeled carriage, and a split trail. It fired a 12-pound high explosive projectile comparable to that of a 75mm gun. However, only high angle fire was possible and its effective range was limited to between 400 (later 300) and 1,800 yards. For traveling, the mortar had a small 215-pound caisson and limber drawn by a mule. By the summer of 1927, three prototype guns and seven mortars had been built. Standardized as the 37mm infantry gun M1 and the 75mm infantry mortar M1, they were issued to the 29th Infantry at Fort Benning for extensive testing.[3]
While it pursued improvements in the infantry’s firepower the Army did not neglect its mobility. In 1925, it introduced a combined water and ration cart that would save one vehicle and driver from each company field kitchen. An examination of the military applications of various commercial motor vehicles led to the tentative adoption of a version of the T-35 Holt tractor, essentially an agricultural vehicle that could haul a 2,000-pound payload in a trailer at up to 10 miles per hour. The Army also tested an improved escort wagon (for rations and baggage) and new infantry and machinegun carts that were about 100 pounds lighter than those that the AEF had used. Additionally, it looked at ways of reducing a soldier’s marching load which World War I experience had proven to be excessive.[4]
The Army constantly updated the organization of the war strength infantry regiment throughout the inter-war period even though, until the mid-1930s most of the changes could only exist on paper. However, the changes made in 1927 were fairly significant. The regiment actually got smaller even though its combat power increased. Its rifle companies changed only slightly (see Appendix 3.10).[5]
Of more importance was the addition of a third platoon to each machinegun company (see Appendix 3.10). Experience in numerous tactical problems had highlighted the fact that eight guns was not enough to provide flank protection and fire support in both offensive and defensive combat. The doctrinal requirement (and practical necessity) to employ guns in pairs further exacerbated the problem but even more compelling was the recognition of the need for additional machineguns to provide anti-aircraft protection. For this reason, the new third platoon would receive heavier .50-caliber machineguns, as soon as any were available.
Although a new machinegun platoon would add more than 100 yards to its parent battalion’s march column Army planners by 1927 appear to have concluded that this was not so great a drawback as they had thought it to be a few years earlier. Organization tables no longer tracked column lengths by this time. However, manpower conservation was still important and the planners were careful to more than offset the manpower requirements of a third machinegun platoon per battalion (which would be configured in exactly the same way as the other two) with economies in the machinegun companies themselves and in other elements of the regiment. The use of more efficient vehicles in regimental and division level transportation also helped. Additionally, the Army sought to increase the machinegun companies’ ability to defend themselves by equipping a small portion of their personnel with rifles. Machinegun strength had further increased by 1931 with the addition of 12 spare guns to each battalion. These would be maintained by the machinegun company but manned by the rifle companies in “defensive” situations.[6]
The biggest change in the battalion headquarters company (see Appendix 3.11) was the reduction in the size of communication (signal) platoon. This was accomplished by combining the courier and message center sections and the radio and the visual signal sections. The battalion intelligence platoon began to develop its own “office force” by sacrificing five scouts and two observers to gain a staff sergeant and a topographical draftsman. The commanding officer’s driver was allocated a cross-country car though nothing like this was actually in service in the Army at this time. The Army was experimenting with several commercial vehicles that seemed to meet the requirements of this type. A motorcycle with sidecar would have been the authorized substitute.[7]
Changes in the regimental headquarters company (see Appendix 3.12) changes paralleled those in the battalion headquarters companies (including a smaller communication platoon).[8] However, the regimental band, now reduced to the more reasonable strength of a warrant officer and 28 men, had been removed from the service company. Not all regiments would have bands. Those that did would place theirs under the regimental adjutant who would attached them to one of the companies for administration and messing.
The regimental service company headquarters was reduced slightly. The staff section of the headquarters platoon remained unchanged but the planners added more cobblers to the supply section so that, in addition to its other functions, it could handle shoe repair for the entire regiment. This allowed the elimination of company-level cobblers and thus saved a total of 10 men per regiment. The use of combined ration-and-water carts in the field kitchens and the removal of most of the spare wagoners made it possible to effect numerous economies in the transportation platoon of both men and vehicles. Although a battalion had more machineguns it was actually allowed fewer combat wagons (four rather than five) but it would get an additional R&B wagon. In view of their responsibilities the chiefs of the transportation sections (assistant wagon masters) were made sergeants rather than corporals.[9]
The howitzer company headquarters received an executive officer and a reconnaissance officer (see Appendix 3.13). A reorganization of the howitzer platoons gave them separate gun, mortar and ammunition squads.[10]
Editor’s Note: The format of the many appendices to this work fit poorly with Substack. For that reason, I have placed them on a PDF file that can be found at Military Learning Library, a website that I maintain.
[1] Mahon & Danysh op cit pp. 48-49; Order of Battle of the United States Land Forces in the World War op cit p 632.
[2] Mahon & Danysh op cit pp. 48-50; Mahon op cit pp. 39-41& 60-61; Weigley op cit pp. 400-402 & 599; and US Army “Index to Tables of Organization” dated 15 August 1927. Unpublished list of tables of organization and authorized strengths of infantry units. A copy is maintained in the Center for Military History in Washington DC; see also War Department Army List and Directory July 1, 1928, (Washington DC, US Government Printing Office 1928) pp. 9-12 & 25-26; see also “Notes from the Chief of Infantry - Re-Organization of the 24th Infantry” and “Re-Organization of the Regiments in Panama” both from Infantry Journal September 1927 p 288.
[3] “Notes from the Chief of Infantry - New Infantry Weapons” Infantry Journal January 1925 pp. 81-82; “Notes from the Chief of Infantry - New Weapons for Howitzer Companies” Infantry Journal November 1926 p. 539; and Captain John K. Rice, Infantry “New Infantry Accompanying Weapons” Infantry Journal April 1928 pp. 376-383.
[4] “Notes From the Chief of Infantry - New Water-Ration Cart” Infantry Journal May 1925 pp. 544-45; “Notes From the Chief of Infantry - Tractors and Cargo Carts” Infantry Journal October 1925 p 429; “Notes From the Chief of Infantry -Experimental Escort Wagon” Infantry Journal January 1927 pp. 64-65; “Notes From the Chief of Infantry - Weight of Pack Reduced” Infantry Journal March 1927 pp. 292-295; “Notes From the Chief of Infantry - M1925E Infantry Cart” Infantry Journal December 1927 p 627.
[5] US Army “Tables of Organization” Table 28 W, “Rifle Company, Infantry Regiment” 23 June 1928. Note that the 23 June 1928 tables superseded those of 11 June 1927, wherein most of the important changes were made. The June 1928 tables are used here because they are more available and, for the infantry regiment at least, almost exactly the same as those of the previous year.
[6] Tables of Organization” op cit; Table 29W “Machinegun Company, Infantry Regiment” 23 June 1928; “Notes From the Chief of Infantry - Three Platoon Machinegun Company” Infantry Journal August 1927 pp. 177-179; and see “The New Infantry Regiment” published in The Infantry School Mailing List Vol XI January 1936, pp. 4, 6, and 16.
[7] US Army “Tables of Organization” Table 27W, “Headquarters and Headquarters Company, Infantry Battalion” 23 June 1928
[8] US Army “Tables of Organization” Table 24W, “Headquarters and Headquarters Company, Infantry Regiment” and Table 23W “Infantry Regiment,” both 27 June 1927.
[9] US Army “Tables of Organization” Table 25W, “Service Company, Infantry Regiment” 27 June 1927.
[10] US Army “Tables of Organization” Table 30W, “Howitzer Company, Infantry Regiment” 23 June 1928.