Kammala jumla mai zuwa: A cikin Grant's Vicksburg Campaign, Logan ya umurci sashen na 3 na James B. McPherson's XVII Corps, wanda shine na farko da ya shiga birnin Vicksburg a watan Yulin 1863 bayan da aka kama shi. Bayan haka Logan ya yi aiki a matsayin gwamnan soja na birnin. A watan Nuwambar 1863 ya yi nasara da William Tecumseh Sherman a cikin umurnin XV Corps; kuma a
Yaƙin Atlanta (22 ga Yuli, 1864), bayan mutuwar James B. McPherson a lokacin rana, ya ɗauki umurnin Sojojin Tennessee. Oliver O. Howard ya sauya shi ba da daɗewa ba. Ya koma Illinois don zaben 1864 amma ya koma sojojin bayan haka kuma ya umurci rundunarsa ta XV a Sherman's Carolinas Campaign.