Arthur is the son of Geoffrey, the next-oldest brother after the late king, Richard the Lionhearted. According to the legal rules of succession, Arthur should be the next in line for the throne. This fact is widely acknowledged by the characters in the play. Even John’s own mother, Eleanor, notes that his right to the Crown isn’t ironclad, telling him, “Your strong possession [is] much more than your right” (1.1.40). As this sentence indicates, however weak his right to the throne may be, John maintains it through his “strong possession,” a phrase that underscores how much fitter John is to rule than the young and inexperienced Arthur. From a historical perspective, Arthur was in fact of marriageable age at the time of the events depicted in the play. However, Shakespeare has chosen to portray this figure as a boy, frequently drawing attention to his youthfulness by having characters refer to his beauty: Constance calls him her “pretty Arthur” (3.4.89), and Hubert likewise addresses him as “pretty child” (4.1.130). Arthur’s youthfulness and emotional immaturity mark him as unfit to rule. Yet they also help clarify why the prospect of his assassination so thoroughly upsets the kingdom.