Sir Edgar is a greedy, evil, pompous and selfish king. He wants nothing more than to be the supreme ruler and has a grudge on Char whom he plans to kill and make himself king.
Role in the film
In the movie, he took care of his nephew and it was revealed that he killed his own brother, who was Charmont's father. His talking snake Heston told him about Ella obedience, which Hattie confirms when Edgar offers Char's hand in marriage. Knowing that Char intends to marry Ella, Edgar orders her to kill him when he proposes and tell no one. When Ella's new friends sneak into the castle to save her, they find out that Edgar is poisoning the crown Char will receive during the ceremony, but Ella bursts in just in time to stop him. Edgar calls for the knights and red guards and a battle ensues. Ella explains everything to Char while battling alongside of him. When Edgar's forces lose, who are caught trying to kill the prince, he admits to the people that he killed the king. However, Edgar says he only deserves the crown and is then carried away by his own rhetoric. Edgar puts the crown on dramatically on his own head and promptly collapses from the poison.
Sir Edgar doesn't exist in the book, and Charmont does not have a known uncle.