Whakaotihia te rerenga e whai ake nei: I te taiwhanga ki te rawhiti, i whakaekea e te Union Army of the Potomac, i whakahaua e te Major General Joseph Hooker, te ope taua o Northern Virginia i whakahaua e General Robert E. Lee i te Pakanga o Chancellorsville. I whakamahere a Hooker ki te neke i te nuinga o tana ope ki muri o nga Confederates i mua i te urupare a Lee me te akiaki i a Lee kia hoki whakamuri engari i whakaroa te ope a te Uniana, ka mutu e tetahi ope Confederate iti, i whakakahahia e te toenga o te ope Confederate. Katahi ka tukuna e Lee tetahi pou whakaeke i arahina e Thomas J. Jackson huri noa i te taha maui o Hooker, i whakaeke i etahi haora i mua o te ra o te ra i te Mei 2; tenei whakaeke me etahi atu whakaeke a te Ropu i te ra i muri mai i akiaki a Hooker ki te hoki mai i te Mei 6. I te wa o te pakanga, i whara a Jackson i te pupuhi a te hoa, a, i mate ia i etahi ra i muri mai. I whakahoutia e Lee tana ope i muri i te pakanga, a, i whakaekehia e ia he whakaekenga o te rohe o te Uniana i te marama o Hune, ka neke atu ma te raorao o Shenandoah ki Pennsylvania; I whakakorehia a Hooker i te 29 o Hune, na te tautohetohe tonu me te kawanatanga mo te hoia o Harpers Ferry, a ka whakakapia e Major General George Meade. I te Pakanga o Gettysburg mai i te Hurae 1 ki te Hurae 3, i angitu a Meade ki te aukati i nga whakaeke a Lee i a ia e patu ana i nga mate nui. I akina a Lee ki te hoki ki Virginia; I whai a Meade i te whai tata engari kaore i taea te kimi i te whai waahi ki te patu i te ope Confederate. I te Oketopa, i ngana a Lee ki te wehe me te whakangaro i a Meade i te Campaign Bristoe engari i rahua i te whakaeke ki nga turanga o te Uniana i te Pakanga o Bristoe Station i te Oketopa 14. I raro i te pēhanga a ngā mana o te Uniana, i ngana hoki a Meade ki te whakaeke i ngā tūnga o Lee
i te taha o te Mine Run; Heoi, i taea e Lee te whakatu i tetahi raina paruru kaha puta noa i te raina whakamua a te Uniana. I whakaaro a Meade he kaha rawa te tuunga o te Rōpū ki te whakaeke, ka hoki whakamuri.