Kammala jumla mai zuwa: Whistler ya yi aiki a cikin Yakin Mexico-Amurka, daga 1846 zuwa 1848, yana shiga cikin Siege na Veracruz, Maris 9 zuwa 29, 1847, Yaƙin Cerro Gordo, Afrilu 17-18, 1847, Yaƙin Contreras, Agusta 19-20, 1847,
Yaƙin Churubusco, 20 ga Agusta, 1847. An nada shi na farko a ranar 20 ga Agusta, 1847 don "Gallant da Meritorious Conduct" a cikin Battles of Contreras da Churubusco, Mexico.