Burnside's Bold Plan: Flanking Lee at Fredericksburg General Ambrose Burnside's plan at the Battle of Fredericksburg aimed to outflank Confederate General Robert E. Lee by crossing the Rappahannock River and attacking Lee’s right wing. Burnside believed a surprise maneuver would catch Lee off guard, but logistical delays, poor coordination, and defensive positions on Marye's Heights thwarted his efforts. Instead of a successful flanking, Burnside’s forces were bogged down in frontal assaults, le