Original: By making the hero of the tale a disobedient and rebellious little rabbit, Potter subverted her era's definition of the good child and the literary hero genre which typically followed the adventures of a brave, resourceful, young white male.
Simplified: At that time, the traditional literary hero was usually a brave, clever, young white male. Yet Peter Rabbit, the hero of The Tale of Peter Rabbit, was a disobedient little rabbit.