Whakaotihia te rerenga e whai ake nei: I te wehenga atu o Alabama me tana ope iti, i tohaina a Reno mo te wa poto ki te whakahau i te Fort Leavenworth Arsenal kia tae ra ano ki te wa i whakatuhia ai ia hei rangatira rangatira mo nga kaitohutohu i te ngahuru o 1861. I whakawhitihia ia ki Virginia, ka riro i a ia te mana o te 2nd Brigade, Burnside Expeditionary Force, a, kaore i roa ka whakahaerehia e ia e rima nga ope taua. I whawhai te 2nd Brigade i roto i te Major General Ambrose Burnside's North Carolina Expedition mai i te Hui-tanguru tae noa ki te Hurae 1862. I riro a Reno hei rangatira wehenga i roto i te IX Corps, kua riro hei waahanga o te Army of the Potomac. I roto i te Campaign Northern Virginia, i kaha te whakahe a Reno ki tana hoa me tana hoa akomanga a Stonewall Jackson i te Pakanga Tuarua o Bull Run me te
Te Pakanga o Chantilly. I tohua a Reno hei rangatira nui i te 20 o Akuhata 1862. (I whakapumautia tenei whakatairanga i muri i te mate i te Poutu-te-rangi 9, 1863, me te ra o te taumata i whakapumautia hei Hurae 18, 1862.) I riro a Burnside hei rangatira mo te parirau matau o te Army of the Potomac mo te timatanga o te Maryland Campaign i te marama o Hepetema, ka eke a Reno ki te rangatira o te IX Corps mai i te Mahuru 3.