The first Scout companies were organized by the US in 1901 to combat the Philippine Revolution led at that time by General Emilio Aguinaldo. In 1919-20, the PS companies were grouped into regiments as part of the US Army and redesignated the 43d, 45th, and 57th Infantry Regiments, plus the 24th and 25th Field Artillery Regiments, the 26th Cavalry Regiment (PS) and the 91st and 92nd Coast Artillery Regiments. Service and support formations were also organized as engineer, medical, quartermaster and military police units. The infantry and field artillery regiments were grouped together with the U.S. 31st Infantry Regiment to form the U.S. Army’s Philippine Division. At this point, the Scouts became the U.S. Army’s front line troops in the Pacific.