ɪn nˈaɪntiːnhˈʌndɹɪd sˈɪkstiːn, ˈæftɚ kəmplˈiːɾɪŋ hɪz sˈɑːfəmˌoːɹ jˈɪɹ ɪn hˈaɪ skˈuːl ɪn kɹˈɛstən, ˈaɪəwə, hiː kənsˈiːld hɪz jˈuːθ ɪn ˈɔːɹdɚ tʊ ɛnlˈɪst ɪnðə mˈɪlətˌɛɹi sˈɜːvɪs, wˌɛɹ hiː fˈɜːst sˈɜːvd wɪððə fˈɜːst ˈaɪəwə fˈiːld ɑːɹtˈɪlɚɹi ɪnðə pˈæntʃoʊ vˈɪlə ˌɛkspədˈɪʃən.
In 1916, after completing his sophomore year in high school in Creston, Iowa, he concealed his youth in order to enlist in the military service, where he first served with the First Iowa Field Artillery in the Pancho Villa Expedition.