Aumerle is the son of the Duke and Duchess of York, and therefore Richard and Bullingbrook’s cousin. He is very much of Richard’s party; though he asks the exiled Bullingbrook to write to him, he is happy to slander him to the King.
Rather a crawler, he overdoes his devotion to Richard somewhat. He accompanies the King to Ireland. When they return to find England almost completely under Bullingbrook’s control, Aumerle attempts to rally the King and give him some hope. He later counsels the King against fighting to the death. He attempts to bluster his way out of being found guilty of his uncle Gloucester’s murder, and later joins a conspiracy to kill Bullingbrook after the latter has become King Henry IV. He quickly repents when he is found out, and his mother’s entreaties save his life. He is not the most intelligent of men, nor the most honorable; arguably he is completely out of his depth in the court.