The US Government formed the Palmetto Regiment to engage in hostilities that arose with the Mexican government. The Citadel graduating class of 1846 trained the junior officers of The Palmetto Regiment prior to their departure for the Mexican War. One member of that class, William Magill, became the first Citadel graduate to serve in the regular US Army joining BG Zachary Taylor's 3rd U.S. Dragoons Cavalry Regiment. He also served in Mexico with two non-graduates (Citadel alumni nonetheless). Both of those, listed below, died from their service in the Mexican War. J. H. Howell, an ex-cadet from the class of 1846, became the first alumnus to fall in battle. Allan Little has a different story: as a result of his heroism during the war, the SC Legislature awarded a full scholarship to Little, and he became The Citadel's first veteran cadet. Little graduated in 1852 as the first Honor Graduate, but he died from the war wounds inflicted on him in 1847.
| Class | Rank, Name, Unit | Battle | Death Date |
|---|---|---|---|
| 1846 | Judah Alexander | June 19, 1847 | |
| 1846 | J. H. Howell (Palmetto Regiment) | KIA, Puebla, Mexico | November 6, 1847 |
| 1846 | McBelton O'Nealle | KIA, Churubrusco, Mexico | |
| 1848 | Pearcall Graham | KIA, Mexico City | November 22, 1847 |
| 1849 | Eugene Wilder | KIA, Perote, Mexico | August 20, 1847 |
| 1852 | Allen H. Little (Palmetto Regument) | WIA, Garita de Belen | August 1854 |