Kammala wannan jumla: Ya shiga rundunar sojojin Tarayyar a matsayin mai zaman kansa a Kamfanin E na 49th New York Volunteer Infantry a watan Yuni, 1861, ya tashi zuwa sandan da aka tsara. Tare da Sojojin Potomac, ƙungiyarsa ta shiga cikin yaƙe-yaƙe waɗanda suka haɗa da Young's Mill, Yorktown, Williamsburg, Mechanicsville, Fair Oaks, Gaines's Mill,
Tashar Savage, Malvern Hill, Bull Run na biyu, Dutsen Kudu, Antietam, Fredericksburg, Williamsport, Gettysburg, Gudun Ruwa, Daji, Cold Harbor, Petersburg da sauransu. An kama Walsh ne a lokacin ayyukan da aka yi a kan Railroad na Welden ba da daɗewa ba kafin ƙarshen lokacin da ya yi rajista kuma ya kasance fursuna a Belle Isle, Libby Prison, Andersonville, Savannah, Castle Pinckney da Florence Stockade, kafin a musayar shi kuma ya koma Annapolis, Indiana, inda aka sallame shi a ranar 5 ga Mayu, 1865. A wani lokaci bayan wannan, ya shafe shekaru takwas yana aiki a " Wisconsin State Journal " a Madison.