Historical Inaccuracies in a Tragical History (or is that Historical Tragedy?)

Scene Depiction Reality
I.i Yorkist victory followed by imprisonment of Hastings and Clarence The Yorkist victory at Tewkesbury occurred in 1471. While there is no evidence of Hastings imprisonment before Richard’s reign, Hastings was in conflict with the Woodeville side of the royal family/government. Clarence was not charged with treason and imprisoned until early 1478.
Richard responsible for Clarence’s suspicion of treason. This had more to do with Clarence’s own actions. With Warwick’s death, Clarence took control over all the Warwick estates (though his marriage to Isabelle Neville, Warwick’s daughter). When Richard married Anne Neville IN 1472, this created a dispute regarding the lands and estates. Edward intervened and divided the estate between his two brothers in 1474. When Clarence attempted to supplement these lands through a marriage to Mary of Burgundy in 1477, Edward refused consent. Clarence then left the court, and because of this, suspicions grew to Clarence’s loyalty. He was arrested for treason in early 1478.
Richard decides to marry Anne Neville for political purposes. Richard married Anne Neville in 1472.
I.ii Richard “woos” Anne over the dead body of Henry VI Never happened. Though according to one account of history, Richard’s wooing was noteworthy. After Henry and Prince Edward’s death, Clarence took Anne (his sister-in-law) as his ward and put her into hiding, from which Richard took her. He then took her to sanctuary and married her the next year. By the time of Clarence’s imprisonment in 1478, not only were Richard and Anne married, but they were also parents to a son Edward, born in 1473.
I.iii Queen Margaret curses the Yorks Queen Margaret had been sent back to France as part of the state settlement following Edward’s failed invasion of France in 1475. She was gone by the time of Clarence’s imprisonment, and would not return to England for the rest of her life. She died in 1482.
Richard hires murderers to kill Clarence Clarence was “privately executed” by the state (after a death sentence).
II.i/II.ii Edward learns of Clarence’s death and subsequently dies. Edward died in 1483, five years after Clarence’s death.
Richard is at the palace when Edward dies. Richard had been in the north of England on a military campaign when Edward died. He returned to London for the funeral. On this trip, Richard’s train meets with young Prince Edward’s train.
III.i Edward arrives in London with Richard; Buckingham calls for young Richard of York to come out of sanctuary; Richard arrives within minutes Edward and Richard arrived in London on May 4, 1483. Young Richard comes out of sanctuary on June 16, 1483.
III.iv Richard accuses Jane Shore of witchcraft Richard, a Puritan, had Shore sent to a church court for her sexual crimes (crimes, at least, in his eyes): being not only Edward IV’s mistress, but also (later) the mistresses of both Hastings and Dorset. She was “convicted” and her penance was to walk through the streets of London in bare feet and a sheet, carrying a candle.

Sound familiar?

It was the same punishment for witchcraft for Eleanor Cobham, wife to Humphrey Duke of Gloucester in The Second Part of Henry the Sixth… could the punishment have caused the confusion in history?

III.vii Richard is to be crowned the day after he accepts the throne Richard accepted the throne on June 26, and was crowned on July 6.
IV.ii Richard orders the deaths of the two princes in the Tower. Uncertain, but the evidence is pretty overwhelming to the contrary. Check out this for more info.
IV.iii James Tyrrel Sir James Tyrrell was a soldier in the army of York through the War of the Roses, and worked for Richard. But he also worked for Richmond, once he became King Henry VII. In 1502, however, Tyrrell was charged with treason, and before execution “confessed” to supervising the killing of the princes.

As for why Tyrrell, Asimov has an interesting theory:

Exactly one reigning king in English history was assassinated. That was William II, who died on August 2, 1100, with an arrow in his back... It might have been an accident, but William was a hated man and everyone considered it to be an assassination. Exactly who did it is not certainly known either, but one mad fled rather than face an inquest, and though he stoutly maintained his innocence (from abroad), common opinion made him the assassin. And who was this man? His name was Walter Tirel and there were rumors that the family of James Tyrrel was descended from this man. Could Henry VII have picked Tyrrell for the role of killer of the princes because he could rely on the populace associating this Tyrrell with the earlier Tirel?

— Asimov, Isaac. Asimov’s Guide to Shakespeare. New York: Doubleday, 1970; page II-601

Queen Anne is dead Queen Anne died on March 16, 1485, eleven months after her and Richard’s son Edward died. Could grief have caused Anne’s death?
IV.iv Queen Margaret gloats over the York women’s fate Not only was she not in England, but she was dead by this time; she wasn’t alive to hear of Richard becoming King of England
Richard speaks to ex-Queen Elizabeth to arrange (or at least agree to) a marriage between him and her daughter Elizabeth No evidence this took place; in fact, on April 11 (less than a month after Anne’s death), Richard publicly denied any plan to marry his niece
V.v Richard is killed in single combat with Richmond Not really. Richard was killed near the end of the battle, when he–after his horse was killed–rushed into a group of the enemy, killing many but dying as a result.

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