Rubuta ci gaba ga wannan sakin layi - Rundunar Sojojin Sojojin Sojoji ta 1 ta koma Philippines a 1908 kuma ta yi garkuwa da Fort Stotsenburg na tsawon shekaru biyu. Wannan ƙaddamarwa ya fi kwanciyar hankali fiye da na ƙarshe, kuma rundunar ta koma gida a ranar 12 ga Fabrairu, 1910. A, B, D, da kuma K Sojoji sun kasance a Presidio na San Francisco kuma daga bisani suka shiga sauran rundunarsu a Presidio na Monterey har zuwa ranar 1 ga Agusta, 1914. Motsawa zuwa Kudancin California, Rundunar Sojoji ta 1 ta yi garkuwa da San Ysidro don mayar da martani ga tashin hankali a kudancin iyakar Mexico. A ranar 24 ga Agusta, 1915, rundunar ta koma Calexico, California don karfafa kan iyaka da kare kanta daga hare-haren da "bandito", Pancho Villa. Sun ci gaba da tsare kan iyaka yayin da Janar Pershing ya kaddamar da Tafiya ta Hukunci
Kuma har yanzu suna can lokacin da Amurka ta shiga yakin duniya na I. Rundunar Sojoji ta 1 ba ta shiga cikin yakin duniya na farko ba, amma ta kasance tana tsaron kan iyaka har zuwa 19 ga Janairu 1923, lokacin da suka tafi Fort D. A. Russell, Texas. Wannan shi ne matsayi na karshe a matsayin doki na doki, kuma a lokacin wani biki a ranar 14 ga watan Disamba, 1932, sojojin sun sauka kuma sun wuce cikin bita, suna gaishe da dawakai yayin da suka bar su don zama na'ura. Motsawa zuwa Fort Knox, Kentucky, 1st Cavalry Regiment ya zama na farko da aka sanya na'ura a cikin sojojin Amurka, kuma an haɗa shi da 13th Cavalry Regiment don samar da Brigade na 7th Cavalry (Mecz). A lokacin rani na 1939, 7th Cavalry Brigade (Mecz) ya shiga cikin Plattsburgh Maneuvers kuma ya taimaka wajen bunkasa dabarun farko na Sojojin don yakin makamai. A lokacin rani na 1940, Louisiana Maneuvers ya tabbatar da rundunar sojan kasar game da bukatar samar da rundunar soji da aka kafa a ranar 15 ga Yuli, 1940. An sake sanya sunan 1st Cavalry Regiment zuwa 1st Armored Regiment a wannan ranar, kuma an sanya shi zuwa 1st Armored Brigade. Ba zai dauki lokaci mai tsawo ba kafin a gwada sabon rundunar sojin Amurka a yaki.