The regular army was supplemented by the National Guards of the various States which had 7,578 regiments with 9,103 commissioned officers and 123,105 enlisted men, or a total organization of 132,208. The "reserve militia," which was in fact little more than a name, consisted of the availables for service between the ages of 18 and 45 years, and estimated on the basis of population, numbered about 20,000,000.
Before there was any real indication that the country would become actively involved in the world war steps were taken to reorganize and develop an efficient army, and under the Act which became effective on July 1, 1916, and which provides for the establishment of basic units for the army, the War Department orders and regulations fixed the basis of the organization as follows:
Sixty-four infantry regiments, 25 cavalry regiments, 21 regiments of artillery, a coast army corps, the brigade division, army corps, and army headquarters, with their detachments and troops. A general staff corps, adjutant general's department, inspector general department, judge advocate general department, quartermaster corps, medical department, corps of engineers, and ordnance department, signal corps, officers of the bureau of insular affairs, militia bureau and detached officers.
The law specifies that the total armed force shall include the regular army, volunteer army, officers' reserve corps, enlisted reserve corps, and the National Guard of the various States, subject to call for duty within the borders of the United States.
The reorganization of the army was being effected at the time Uncle Sam was called to fight for humanity, and only an approximation of the condition can be made, for about two-thirds of the National Guard had been taken into the regular service incident to the trouble with Mexico, when the Guardsmen were summoned to the border to protect the country, and recruiting was proceeding in all branches of the service to bring all the regiments up to a war footing.
UNITS ON WAR FOOTING.
The various units, on a war footing, are: Infantry regiment, 1,800 men; cavalry regiment, 1,250 men; field artillery, light regiment, 1,150; field artillery, horse regiment, 1,150; field artillery, heavy regiment, 1,240; field artillery, mountain regiment, 1,100; engineers, pioneer battalion, 490; engineers, pioneer battalion, mounted, 270; engineers, pontoon battalion, 500; signal troops, field battalion, 160; signal troops, field (cavalry) battalion, 170; signal troops, aero squadron, 90 men. Trains—infantry division: ammunition, 260; supply, 190; sanitary, 530; engineer, 10. Cavalry: ammunition, 60; supply, 220; sanitary, 300.
A division of infantry consists of 3 brigades of infantry, 1 cavalry regiment, 1 artillery brigade, 1 regiment of engineers, 1 field signal battalion, 1 aero squad, 1 ammunition train, 1 supply train, 1 engineer's train and 1 sanitary train, and comprises approximately 22,000 men and 7,500 horses and mules, and 900 vehicles, including guns. The latter figures are, however, changed by reason of the introduction of motor trucks, and automobiles, there being a consequent reduction in the number of horses and mules and a slight increase in the number of men.
A cavalry division consists of 3 cavalry brigades, 1 regiment of field artillery, 1 battalion of mounted engineers, 1 field signal battery, mounted; 1 aero squadron, 1 ammunition, 1 supply, 1 engineer and 1 sanitary train.
A brigade, in the main, consists of three regiments, the infantry having 5,500 men, cavalry brigade 2,500 and artillery brigade 2,500 men.