9 . ▁ ▁The ▁thousands ▁of ▁photograph s ▁which ▁Mat hew ▁Br ady ' s ▁photograph ers ▁( such ▁as ▁Alexander ▁Gard ner ▁and ▁Tim othy ▁O ' S ull ivan ) ▁took ▁have ▁become ▁the ▁most ▁important ▁visual ▁documentation ▁of ▁the ▁Civil ▁War , ▁and ▁have ▁helped ▁histor ians ▁and ▁the ▁public ▁better ▁understand ▁the ▁era . ▁ ▁Br ady ▁photograph ed ▁and ▁made ▁port ra its ▁of ▁many ▁senior ▁Union ▁officers ▁in ▁the ▁war , ▁including : ▁▁ ▁U ly ss es ▁S . ▁Grant ▁ ▁Nathan iel ▁B anks ▁ ▁Don ▁Carlos ▁Bu ell ▁ ▁Am bro se ▁Burn side ▁ ▁Benjamin ▁Butler ▁ ▁Josh ua ▁Chamber lain ▁ ▁George ▁C uster ▁ ▁David ▁Far rag ut ▁ ▁John ▁Gib bon ▁ ▁Win field ▁Han cock ▁ ▁Samuel ▁P . ▁He int zel man ▁ ▁Joseph ▁Hook er ▁ ▁Oliver ▁Ot is ▁Howard ▁ ▁David ▁Hunter ▁ ▁John ▁A . ▁Log an ▁ ▁Ir vin ▁Mc D ow ell ▁ ▁George ▁McC le ll an ▁ ▁James ▁Mc Ph erson ▁ ▁George ▁Me ade ▁ ▁Mont gom ery ▁C . ▁Me igs ▁ ▁David ▁D ixon ▁Por ter ▁ ▁William ▁Rose cr ans ▁ ▁John ▁Sch of ield ▁ ▁William ▁Sh erman ▁ ▁Daniel ▁S ick les ▁ ▁Henry ▁Warner ▁S loc um ▁ ▁George ▁St on eman ▁ ▁Ed win ▁V . ▁Sum ner ▁ ▁George ▁Thomas ▁ ▁Em ory ▁U pton ▁ ▁James ▁W ad sw orth ▁ ▁Lew ▁Wal lace ▁ ▁On ▁the ▁Confeder ate ▁side ,