Who is Oliver O. Howard from Gods and Generals and what is their importance?

Oliver O. Howard was a general in the Union Army. He lost an arm at the battle of Fair Oaks, commanded a division at the Battle of Fredericksburg, and he then commanded the Eleventh Corps at Chancellorsville. Howard incorrectly believed that his unit was far away from the battle, thus, he failed to order trenches prepared, leaving his men unprotected and lacking in defense. Thus, they are easily overrun when Jackson makes a surprise attack on his right flank.