Mezue ahịrịokwu na-esonụ: N'afọ 1914, a kpọrọ ngalaba ahụ ngalaba nke asaa dị ka akụkụ nke nnukwu nhazi nke National Guard. N'abalị iri abụọ na itoolu n'ọnwa Juun n'afọ 1916, a kpọkọtara ndị agha nke asaa na Ugwu Gretna ma kpọga ha El Paso, Texas, ka ha jee ozi n'ókè Mexico dị ka ndị agha na-ahụ maka ndị agha.
Njem Nleta Ahụhụ ahụ banyere Mexico. Major General Charles M. Clement nyere iwu, na-eduzi Brigade nke Mbụ nke gụnyere 1st, 2nd, na 3rd Regiments, Brigade nke Abụọ nke 10th, 16th, na 18th Regiments, na Brigade nke Atọ nke 4th, 6th, na 8th Regiments. E nwekwara ndị agha na-agba ịnyịnya na otu ndị agha na-agba égbè, tinyere ụlọ ọrụ abụọ nke ndị agha na-agbasa ozi na ndị ọrụ ahụike. Ogige ahụ dị n'èzí El Paso nwetara aha 'Camp Stewart' n'aha onye isi ndị agha, Thomas J. Stewart. Na Septemba 19, e zigara otu brigade n'ụlọ. Na November 14, ndị 1st Artillery hapụrụ ụlọ; ndị 18th Infantry hapụrụ Pennsylvania na Disemba 18; na ndị fọdụrụ nke nkewa n'etiti 2-19 Jenụwarị 1917. O yiri ka ihe ka ọtụtụ n'ime ndị otu ahụ enweghị ọrụ na 23 February 1917 na Philadelphia.