Richard III was probably not nearly as bad a man as
William Shakespeare's play portrays him to be -- remember, Shakespeare was writing to please
Elizabeth I, granddaughter of the man who deposed Richard. At least he was no worse than many other English kings. Legend and Shakespeare say that Richard was a
hunchback, which is a great exaggeration of the truth (that he had one
shoulder higher than the other). He fought for his brother
Edward IV on the Yorkist side of
the War of the Roses at the
Battle of Tewkesbury, where
Henry VI's son Edward died. Richard married that Edward's
widow Anne.
Richard became king in 1483 as a result of the assertion by the Bishop of Bath and Wells that Edward IV's marriage to Elizabeth Woodville had not been legal and thus his son Edward V was illegitmate and shouldn't be king. The people asserting this in Parliament basically didn't like the Woodville family and wanted them out of power; Richard did not engineer the entire thing.
Unfortunately, Richard and Anne's son Edward died in April 1484 and Anne less than a year after. Richard sought to name his nephew as heir to the throne, but The War of the Roses flared up again after a series of Yorkist kings, and Henry Tudor, third cousin once removed to Henry VI, was supported by the Lancaster side (though his claim to the throne was a stretch). Both gathered their armies and ended up meeting at Bosworth Field on 22 August 1485. Richard was killed and his helmet placed on Henry Tudor, now Henry VII's head.