Who is Ambrose E. Burnside from Gods and Generals and what is their importance?

Major General Ambrose Burnside commanded the ninth corps of the Union Army. He was considered by most to be a good corps commander, but he completely choked under the pressure of full command of the army. Burnside made a plan to outmaneuver Lee, but a delay in the arrival of pontoon bridges did not allow his forced to cross the Rappahannock River at the designated time. Unfortunately, Burnside refuse to look for other alternatives, and the battle near Fredericksburg is a complete disaster. Burnside was then removed from command.