Rubuta ci gaba ga wannan sakin layi - Gibbon ya dawo a matsayin kwamandan na 2nd Division a lokacin Janar Grant na Kamfen na Overland a watan Mayu da Yuni 1864, yana ganin aikin a yakin basasa, Spotsylvania Court House, da Cold Harbor. A ranar 7 ga Yuni, 1864, an daukaka shi zuwa babban janar na masu sa kai. A lokacin yakin Siege na Petersburg na gaba (Yuni 1864 zuwa Afrilu 1865), Gibbon ya zama abin takaici lokacin da sojojinsa suka ƙi yin yaƙi a tashar Ream
a watan Agusta na shekara ta 1864. Ya yi umurni na ɗan gajeren lokaci na XVIII Corps kafin ya tafi hutu na rashin lafiya, amma aikinsa yana da mahimmanci, ya koma ya umurci sabon kwamandan XXIV Corps a cikin Army of the James. Sojojinsa sun taimaka wajen cimma nasara a yakin na uku na Petersburg a watan Afrilu na shekara ta 1865, inda suka kama Fort Gregg, wani ɓangare na tsaro na Confederate. A lokacin yakin Appomattox, ya taimaka wajen toshe hanyar tserewa ta Confederate a yakin Appomattox Courthouse, wanda ya haifar da janar Lee ya mika wuya. Ya kasance daya daga cikin kwamishinoni uku don mika wuya na Confederate.