After years of civil unrest between the royal Houses of York and Lancaster, the Yorkist Edward IV is undisputed king. His brother, Richard Duke of Gloucester, plots to seize the throne for himself, removing anybody in his path. Richard decides he needs a wife and sets out to woo Lady Anne, widow of Henry VI's heir. Against all the odds he wins her and celebrates by having his brother Clarence covertly killed in the Tower. On hearing of Clarence's death, Edward IV is taken ill and dies. In his new role as Lord Protector, Richard has Edward's heirs confined in the Tower, supposedly for safe-keeping and to await the coronation. Edward IV's widow, Queen Elizabeth, mistrusts Richard and is proved right when he orders the execution of her brother Rivers and son (by her first marriage) Grey. The Duke of Buckingham becomes Richard's chief adviser and together they mastermind and manipulate Richard's accession to the throne. Richard promises Buckingham an earldom for his help but refuses to grant it when Buckingham will not kill the princes held in the Tower. Richard finds other killers. Fearing for his safety, Buckingham flees to join the last Lancastrian heir Henry Tudor, Earl of Richmond, who is leading an army from France against Richard. Having willed the death of his wife Anne, Richard plans to marry Edward IV's daughter (also Elizabeth, not seen in the play) in order to prevent Richmond from doing so and thereby strengthening his claim to the throne; Queen Elizabeth tricks him by pretending that she will assist him in this. Richmond and his followers arrive in England and the two armies' camp close at Bosworth Field. The night before the battle, the Ghosts of his victims torment Richard in his dreams. The next day Richard is killed in battle and Richmond claims the crown as Henry VII. He announces he will marry Elizabeth of York and finally unite the two warring factions.
The historical Shakespearean plays were the product of de Vere's arrangement with Queen Elizabeth in which she paid de Vere an annuity of £1,000 and in return de Vere writes propaganda plays for the masses to promote the virtues of and loyalty to the regime.
The purpose of this particular play was to legitimize the Tudor regime and Queen Elizabeth in its first victory, namely the overthrown of Richard III by Henry Tudor.
The play celebrates Queen Elizabeth with the concluding speech:
... the lamp that keeps fair England's light,
And through her faith her country lives in peace:
And she hath put proud Antichrist (Catholic Spain) to flight,
And been the means that civil wars did cease.
There is an uncanny resemblance between the humpbacked usurper Richard III and Robert Cecil.