The True Tragedy of Richard III a source for his play, though the majority tend to favour this judgement. Geoffrey Bullough treats "The True Tragedy" as a "probable source" for "Richard III", citing several commonalities (as when, in both plays, Richard calls for a horse on Bosworth Field, yet refuses to flee the battle) — though Bullough admits that the nature of the plays' relationship is "not clear." The uncertainty in dating has allowed a few commentators to propose a reversed priority, and to argue that the author (or reviser) of "The True Tragedy" may have borrowed from Shakespeare's play. Shakespeare appears to have known of
Richard III (play) in full swing, and Richard is left at a disadvantage. Richard is soon unhorsed on the field at the climax of the battle, and cries out, "A horse, a horse, my kingdom for a horse!" Richmond kills Richard in the final duel. Subsequently, Richmond succeeds to the throne as Henry VII, and marries Princess Elizabeth from the House of York. "Richard III" is believed to be one of Shakespeare's earlier plays, preceded only by the three parts of "Henry VI" and perhaps "Titus Andronicus" and a handful of comedies. It is believed to have been written c. 1592–1594. Although "Richard