Whakaotihia te rerenga e whai ake nei: I te timatanga o te Pakanga o Amerika, i mahi a Sedgwick hei koroneela me te kaiawhina o te kaitiaki o te Tari Hupirimi o Washington. I ngaro ia i nga mahi tuatahi o te pakanga i te Pakanga Tuatahi o Bull Run, i te whakaora mai i te mate pukupuku. I whakatairangahia ia ki te brigadier general i te Akuhata 31, 1861, i whakahau ia i te 2nd brigade o te Maj. Gen. Samuel P. Heintzelman's division i roto i te Army of the Potomac, ko tana ake wehenga, i tohua ko te wehenga tuarua o te II Corps mo te Peninsula Campaign. I Virginia, i whawhai ia i Yorktown me
E whitu nga Pini. I te Pakanga o nga Ra e whitu, i whawhai te wehenga a Sedgwick i te teihana o Savage me Glendale, i whara i te pakanga whakamutunga. Whai muri i nga Pakanga o nga Ra e whitu, i whakatairangahia ia hei rangatira nui. Ko te II Corps me te wehenga a Sedgwick kaore i uru ki te Campaign Northern Virginia.