On the U.S. side, the war was fought by regiments of regulars and various regiments, battalions, and companies of volunteers from the different states of the Union as well as Americans and some Mexicans in the California and New Mexico territories.
Na američkoj strani, rat su vodile pukovnije redovne vojske, kao i razne pukovnije, bojne i satnije dragovoljaca iz raznih saveznih država, kao i Amerikanci i neki Meksikanci na području Kalifornije i Novog Meksika.