Editing Philippine Division (United States) (section)

==History==
[[File:United_States_World_War_II_(Square)_Infantry_Division_1940_Structure.png|thumb|right|Square Division example: 1940 US Infantry Division. On the far left can be seen two Brigades of two Regiments each]]The Philippine Division was constituted in the Regular Army on 7 December 1921 and activated at Fort William McKinley, Philippine Islands, on 10 April 1922. The division was the primary ground force of the Philippine Department and was given the mission of defending the Philippine archipelago from potential invaders. The division began organizing around the nucleus of the 23rd Infantry Brigade (consisting of the 45th and 57th Infantry Regiments), which was activated on 15 December 1921. Additionally, the 31st Infantry, the 1st Battalion, 24th Field Artillery, the 1st Battalion, 14th Engineers, and several of the companies in the division special troops were already organized and integrated into the division. The division continued to receive and activate units throughout 1922, adding HHC, 24th Infantry Brigade; HHC, 12th Field Artillery Brigade, Headquarters, Philippine Division Quartermaster Train, and several of the train’s elements, and the 12th Motorcycle Company by April. The [[15th Infantry Regiment (United States)|15th Infantry Regiment]] was assigned to the division in July 1922, however, only the 1st Battalion was stationed in the Philippines. The remainder of the regiment was posted to the American Barracks in [[Tianjin|Tientsin]], [[China]], and attached to Headquarters, American Forces in China. By the end of 1922, the 12th Medical Regiment was activated and rounded out the division’s structure. The Philippine Division was forced to inactivate several units over the interwar years due to budget decreases, starting with the 12th Field Artillery Brigade headquarters in 1922, followed by the 1st Battalion, 15th Infantry in 1929, and the 24th Infantry Brigade headquarters in 1930. With the relief of the 31st Infantry from the division in 1931, the 24th Infantry Brigade was redesignated as a Philippine Scout (PS) organization and the 43rd and 44th Infantry Regiments (PS) were added to the brigade as inactive units. Additionally, the inactive 25th Field Artillery (PS) was relieved and the 23rd Field Artillery (PS) replaced it as the division’s other indirect fire regiment, also in an inactive status. 

Like other overseas divisions at the time, the Philippine Division was fortunate in that it was located on the terrain on which it would fight if the archipelago was ever invaded. Therefore, the training in which it participated tended to be more realistic and provided a more focused military environment. The environment helped to develop many of the Army officers who would lead the United States to victory in World War II. Due to the archipelago’s seasonal weather patterns, the division conducted individual training, marksmanship training, and schools for specialists during the rainy months of June–August. The drier months of September–November were devoted to officer and noncommissioned officer schools, garrison work details, inspections, and maneuver preparation. The late part of the year began with small unit training, reconnaissance of the maneuver areas for the next major department exercise, and exercising transportation and communications systems. These activities were followed by the repair and construction of roads leading to and on the peninsula of Bataan. The preparations finally culminated in the large-scale division and department maneuvers in January and February. The maneuvers occasionally included large surface squadrons from the Navy as well as amphibious invasion forces provided by the [[US Marine Corps]]. 

In 1933, the Philippine Division began to train in earnest to prepare for an invasion, which Army planners believed would come at the beaches of [[Lingayen]]. The January 1934 maneuver was actually little more than a thorough reconnaissance of the [[Bataan]] peninsula with particular emphasis on the [[Miraveles Mountains]]. This reconnaissance revealed the poor internal road net of the peninsula, and the 14th Engineers and 23rd Field Artillery were put to work improving the trails and roads. The 1935 maneuver was again held on Bataan. This exercise focused on determining the enemy avenues of approach and selecting defensive positions to block those approaches. The 1936 maneuver came uncannily close to rehearsing what would occur 6 years later when the Japanese invaded. The 26th Cavalry, with the 23rd Field Artillery in support, was sent to scout the Lingayan landing areas and report movements of the invasion force, while the Philippine Division concentrated near [[Fort Stotsenburg]]. As the enemy forced the cavalry back, the Philippine Division fought a delaying action, fell back onto Bataan to defend the Olongopo Road, and then centered its defense on the Miraveles Mountains where the exercise ended.

The next change to the division’s structure came in 1936 with the reorganization of the Quartermaster Train into the 12th Quartermaster Regiment. Shortly before Pearl Harbor, the 31st Infantry was reassigned to the Philippine Division, and the 1st Battalions of the 43rd Infantry and the 23rd Field Artillery were activated. Interestingly, the 24th Infantry Brigade was still assigned as an inactive unit; therefore, the Philippine Division was the only Regular Army infantry division that retained the “square” structure (at least on paper) on entry into World War II. The location of the division headquarters on 7 December 1941 was Fort William McKinley.<ref>{{cite book|last=Clay|first=Steven E.|date=2010|title=U.S. Army Order of Battle, 1919-1941, Volume 1. The Arms: Major Commands and Infantry Organizations, 1919-41|location=Fort Leavenworth, KS|publisher=Combat Studies Institute Press|pages=287}}{{source-attribution}}</ref>

===Organization (July 1941)===

{| class="wikitable"
|+
|-
! Unit !! Officers !! American enlisted !! Philippine Scouts (PS) enlisted !! Total
|-
| HHC, Philippine Division || 30 (incl. 2 PS officers) || 4 || 147 || 181
|-
| HQ, Special Troops || 5 (incl. 2 PS officers) || || 5 || 5
|-
| 12th [[Military Police Corps (United States)|Military Police]] Company (PS) || 5 || 45 || 86 || 136
|-
| 12th [[United States Army Ordnance Corps|Ordnance Company]] (PS) || 3 || || 139 || 142
|-
| 12th [[Signal Corps (United States Army)|Signal]] Company (PS) || 10 || || 217 || 227
|-
| [[31st Infantry Regiment (United States)|31st Infantry Regiment]] (assigned December 1941) || 114 || 1,986 || || 2,100
|-
| 23rd Infantry Brigade (PS) || || || ||
|-
| [[45th Infantry Regiment (PS)]] || 117 (incl. 3 PS officers) || || 2,148 || 2,265
|-
| [[57th Infantry Regiment (PS)]] || 118 (incl. 1 PS officer) || || 2,161 || 2,279
|-
| ''24th Infantry Brigade (PS)'' || ''Brigade headquarters inactive'' || || ||
|-
| 1st Battalion, [[43d Infantry Regiment (United States)|43rd Infantry Regiment (PS)]] || 16 || || 313 || 329
|-
| [[23d Field Artillery Regiment (PS)]] ([[QF 2.95-inch mountain gun]]) || 10 || || 391 || 401
|-
|[[24th Field Artillery Regiment (PS)]] ([[75 mm gun M1917|M1917 75mm gun]]) || 39 (incl. 5 PS officers) || || 804 || 843
|-
|14th [[United States Army Corps of Engineers|Engineer]] Regiment (PS) || 24 (incl. 1 PS officer) || || 846 || 870
|-
| 12th [[Medical Corps (United States Army)|Medical]] Regiment (PS) || 22 || || 399 || 421
|-
| 12th [[Quartermaster Corps (United States Army)|Quartermaster]] Regiment (PS) || 18 (incl. 1 PS officer) || || 574 || 592
|- 
| 4th [[Veterinary physician|Veterinary]] Company (PS) || 1 || || 10 || 11
|}