King Richard III
Richard III is the main character of the play that bears his name, though he becomes king only partway through, after his brother Edward has died and he has arranged for his brother and nephews (all prospective heirs to the throne) to be murdered. Richard is among the most infamous and charismatic villains in Shakespeare's body of work, distinctive both for his physical appearance (he is deformed by a hunched back), his ruthless political manipulations, and his treacherous way with words. Unlike his henchmen Hastings and Buckingham, who at least have some qualms about murdering the royal family, Richard is an unrepentant killer. Only in Act 5, as the ghosts of his victims haunt him one by one, does Richard experience pangs of conscience. Conflicted and troubled, he takes to the battlefield and is slain by the Earl of Richmond.
Lady Anne first appears onstage during the funeral procession of her father-in-law, King Henry VI. Her mourning is laced with curses against Richard, who has killed both her father-in-law and her husband. When Richard then attempts to woo her, her first reaction is understandably one of disgust. Eventually, she relents and becomes his wife—and later, his queen. Anne finds little satisfaction in her marriage to England's most powerful man: she realizes Richard has married her not for love, but as a matter of political convenience. Her worst fears are realized when Richard has her killed, then spreads rumors she has died of an illness.
From Act 1 onward, Queen Elizabeth is established as one of Richard's most powerful enemies, not least because she is married to the reigning monarch. After King Edward dies, Richard turns the tables on Elizabeth by killing off her relatives; she, in turn, seeks sanctuary for herself and (unsuccessfully) for her children. Elizabeth nurses a bitter hatred of Richard throughout the remainder of the play, but she reluctantly gives her assent to a marriage between Richard and her daughter, the Lady Elizabeth, possibly to avoid more bloodshed. However, Richard is killed in battle before the wedding can take place.
Duke of Buckingham
The Duke of Buckingham is the most capable and ruthless of Richard's noble henchmen. He might be described as Richard's "star student," since he seems to grow more devious and resourceful with each passing scene. He serves Richard in the hope of gaining additional lands and wealth, not out of any abiding sense of loyalty. Ultimately, Buckingham's defection from Richard is motivated by a combination of conscience and greed. When asked whether he will consent to the murder of Prince Edward, he initially refuses. He then briefly reconsiders, only to turn his back on Richard permanently when he realizes the fragility of their alliance after Richard fails to grant him promised lands and property. This decision leads quickly to his capture and execution.
Earl of Richmond
Although the Earl of Richmond does not appear onstage until Act 5, he is constantly mentioned in Act 4 as an increasingly powerful rival to Richard. As Richard grows more tyrannical, more and more noblemen defect to Richmond, bringing their armies with them. Even before his victory at Bosworth Field, Richmond's supporters characterize him as the moral opposite of Richard: a virtuous leader whose reign will bring peace to England. As if to prove their point, Richmond takes the Lady Elizabeth as his wife, uniting the Houses of York and Lancaster after 30 years of feuding.
Queen Margaret appears in only two scenes, but leaves an indelible impression: it is she who curses Richard and others who are responsible for the death of her husband and son, prophesying their deaths. Her prediction comes to pass as those she has cursed drop dead or suffer terribly, one after the next, climaxing in Richard's demise. In many respects, the character of Queen Margaret embodies the sorrow, anger, and desire for vengeance of several other characters in the play who Richard has done wrong, such as Queen Elizabeth. She is such a powerful and effective speaker that Queen Elizabeth asks Margaret to teach her to invoke curses the same way.