Tuhia he haere tonu mo tenei whitianga - I whakatairangahia a Greer ki te rangatira rangatira, a, i mahi ia i te 1862 ki te 1863, a, i whakauruhia ki te Rear Admiral David Dixon Porter's Mississippi Squadron. I a ia e tohutohu ana i ngā kaipuke rino, i uru ia ki te pakanga o Vicksburg me te whakapae o Grand Gulf
tae atu ki te haerenga a te Union Red River i te timatanga o te tau 1864.