Rubuta ci gaba don wannan sakin layi - Ya kasance a kan iyaka, garrison, da aikin injiniya har zuwa 1846, lokacin da ya shiga aikin soja na sabuwar jihar Texas. Daga bisani, ya yi aiki a lokacin yakin Mexican-American, yana da kwarewa a matsayin kyaftin din da kuma manyan mutane a cikin wasu batutuwa masu muhimmanci ciki har da Battle of Palo Alto.
da kuma yakin Resaca de la Palma. Ya yi aiki a matsayin shugaban ma'aikatan Major Folliott T. Lally a kan tafiya daga Vera Cruz zuwa Mexico City a 1847. Ya shiga kungiyar Aztec ta 1847 a 1871.