AGF Study, NO. 3: Ground Forces In The War Army A Statistical Table

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NOTE ON THE TROOP BASIS

The troop basis was issued at intervals by the War Department to the higher planning agencies of the Army. Its preparation and continuing revision were responsibilities of G-3, War Department General Staff, acting with advice from other agencies of the War Department and from the three major commands. The headquarters of the Army Ground Forces participated actively in discussions of the troop basis until the fall of 1943. After that date, as the overseas theaters were increasingly built up and as strategic plans for the employment of ground forces took more definite shape, the main influence in determining the AGF section of the troop basis passed to the Operations Division, War Department General Staff. Through the Operations Division the desires of theater commanders were mediated to the War Department.

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It was primarily an outline of the kind of Army authorized to exist. First, it stated the number of units of each type authorized to exist by a specified date in the future. This number was determined by anticipation of general war strategy and operational needs and by estimate of the manpower and equipment available and of the length of time necessary for training. Second, the troop basis also stated the number of units of each type already authorized to exist, i.e., units already activated or mobilized. (“Active”, “activated”, “mobilized”, and “already authorized to exist” have substantially the same meaning in the present table and its accompanying interpretation.) As the troop basis developed in form, it stated the number of units already mobilized on the day before the date of the troop basis. For example, the troop basis of 1 July 1943 stated the number of units with table of organization strength, both as projected for 31 December 1943, and as already mobilized on 30 June 1943. The difference, for each type of unit, between the number of units already mobilized and the number authorized to exist by the future date to which the troop basis was projected, indicated the number of units of that type to be activated (or inactivated) during the period for which the troop basis of a given date was drawn up. The troop basis thus constituted the program of mobilization. At first, it was essentially a program for the expansion of the Army. After the Army attained its contemplated strength (at the beginning of 1944) the troop basis was still the program of mobilization in the sense that it indicated readjustments to be made within a fixed total, stating what new units should be activated and what old units inactivated, without further enlargement of the Army, to meet current views as to changing operational needs.

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of the troop basis figure for mobilized strength on that date. The War Department had therefore to devise other methods of personnel accounting. These may be traced in the weekly Minutes of the General Council for 1944.

In its primary function, as an outline of the kind of Army authorized to exist, the troop basis gave an accurate picture. For example, while we can obtain no actual strengths from the troop basis, we may accept at face value the indication of the troop basis of 24 November 1942 that on that date 100 divisions were authorized for mobilization by the end of 1943, or the indication in the troop basis of 1 April 1945 that 89 divisions were mobilized on 31 March 1945 and that their table of Organization enlisted strength was 1,124,738. It is only in this connection, in which the troop basis gives a true picture, that it is used in the present table.

In form the troop basis went through a succession of changes, becoming with each change more elaborate and detailed. In 1942 it was issued in typescript at irregular intervals in a few copies only. By late 1944 it was compiled by machine records methods, issued monthly, and circulated in some 200 copies. These changes are without importance for the present table. Until the last months of 1943 the troop basis gave detailed listing only for tactical units, showing only rough figures for overhead, replacements, nonavailables, etc.; and it listed tactical units of the Ground and Service Forces only, showing only a bulk allotment for the Air Forces. After the end of 1943 Air Forces were listed in the same manner as Ground and Service Forces, and overhead and related requirements were shown with increasing detail. These changes likewise are without significance for the present table, since the table gives only bulk figures for Air Forces and for overhead, etc.

Other changes in the form and content of the troop basis have raised problems in the preparation of the table. Until the end of 1943 the troop basis showed enlisted strengths only. Thereafter enlisted, warrant officer, nurse, officer, and aggregate strengths were given in separate columns. Since for purposes of the present table the figures for earlier and later dates must be comparable, and since only enlisted strengths are available for the earlier period, the table is limited to enlisted strengths throughout.

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combat and service troops and to classify service troops into those employed in close conjunction with combat troops and those employed in rear area support. At first the troop basis carried no indication of these classifications. By October 1944 it indicated them all. But for all dates prior to October 1944, and hence the entire formative period of the Army, computation has been necessary, using troop basis figures as raw material, to obtain the figures desired for the present table on classification as between combat and service units.

Service units in 1942 were not distinguished as pertaining to the Army Service Forces (then Services of Supply) or to the Army Ground Forces. No such distinction was therefore drawn in the troop basis in 1942. In the months beginning with October 1942 all service units (except Air Force) were divided between the Army Service Forces and the Army Ground Forces for activation and training. Service units intended for close support of combat troops, i.e., for inclusion in field armies and employment in the combat zone, were designated as pertaining to the Army Ground Forces. Service units intended for less direct support of combat troops, i.e., for employment in the communications zone, were designated as pertaining to the Army Service Forces. The troop basis of 1 July 1943, and all succeeding troop bases, grouped the two types of service units separately. Henceforth the Army Ground Forces section of the troop basis included units of both combat and service types, and the Army Service Forces section of the troop basis (which included no combat units) included only those service units designated as of ASF type.

Figures in the table for ASF service units, for dates beginning with 30 June 1943, are therefore copied directly from pertinent troop bases without modification. Figures for ASF service units before 30 June 1943 (specifically for 24 November 1942 and 30 December 1942) have been obtained by extracting from the undifferentiated lists of service units in pertinent troop bases those service units designated as ASF in the troop basis of 1 July 1943.

Figures in the table for AGF service units, for dates beginning with 30 June 1943, cannot be copied from pertinent troop bases without modification, as can figures for ASF service units, because AGF service units, as listed in the troop basis, included some units of combat type. Figures in the table for AGF service units, for dates beginning with 30 June 1943, represent the total of units of service branches (chemical, engineer, medical, military police, miscellaneous, ordnance, quartermaster, and signal) attributed to the Army Ground Forces in the Troop Basis, but modified by deduction

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of certain units (chemical, engineer, signal) considered by the War Department to be of combat type, according to definitions noted in the following paragraph. Figures for AGF service units for 24 November 1942 and 30 December 1942 represent what is left, from the undifferentiated list of service units in pertinent troop bases, after removal of both combat units on the one hand and ASF units on the other.

The troop basis did not identify combat units as such until October 1944, but the War Department laid down a definition of combat units for statistical purposes in Circular 422, 29 December 1942. This Circular, as amended by Circular 66, 5 March 1943, has been followed in the preparation of the table. Combat units are defined as:

The values in column 23 have been obtained by adding the figures given in the troop basis for (nondivisional) headquarters, armored, cavalry, coast artillery, field artillery, infantry and tank destroyer units, and such amounts of chemical, engineer, and signal units as are appropriate after combat units of these branches are deducted from the totals for AGF units of these branches given in the troop basis.

Definition of combat units, when introduced into the troop basis on 1 October 1944, followed a new Circular, No. 356, WD, 2 September 1944, which in turn followed closely, with some elaboration, the definitions laid down in Circular 422, 1942. Since the definitions of September 1944 were made after most of the calculations for the present table had been completed and since they varied from earlier definitions in only a minor way, and since there

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was no assurance that the definitions of 1944 would have more permanent historical significance than those of 1942, no attempt has been made to recast the present table to conform to the distinctions introduced into the troop basis in October 1944. And since later and earlier figures in the table must be comparable, referring at all dates to the same thing, the strength of combat and service units has been computed in the table, for dates subsequent to October 1944, in the same manner as for prior dates, no use being made of the indications as to category given in troop bases beginning with October 1944.

The present table would not be greatly different if the categories introduced in October 1944 had been used in its preparation, or if they had been available as far back as 1942. Seven categories, called “missions”, were introduced in the troop basis of 1 October 1944. Only four of these applied to tactical units, the other three applying to replacements and overhead. The four applying to tactical units were substantially equivalent (not counting the Air Forces) to the categories set up in the present table. The seven categories and their equivalents were as follows, not counting the Air Forces:

“Combat Support” referred mainly to certain engineer and signal units, considered as combat units in the present table; but it included also a few other units of the AGF services and all military police of AGF type, considered as service units in the present

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table. It likewise included a small percentage of ASF units. Hence when units whose mission was defined as “Combat” or as “Combat Support” by the War Department in September 1944 are added together, the total is somewhat larger than the total for combat units in the present table. Figures for mobilized enlisted strength for 30 March 1945 are as follows, so arranged as to show the equivalence between the two systems of definition:

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Aggregate strength of the entire Army was distributed as follows on 31 March 1945, as shown by the troop basis of 1 April 1945.

Or in percentages:

Actual strength of the Army was reported to be 8,157,386 officers and men on 31 March 1945, about 4 percent in excess of troop basis strength. Most of the overstrength was in overhead and in replacements (classified under “Training” above). Percentage of the strength of units --- combat, combat support, combat service support, and service support --- would thus be somewhat less than indicated above if computed on the basis of actual strength.

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	Last updated 1 July 2005