Shakespeare described Richard II as a "hunchback" with "a limp and a withered arm"
The body of the king was unburied recently and it was proved through testing and reconstruction that he had a serious illness in his spine that made him walk bent. So Shakespeare's physical potrayal of him seems to be at least partially correct.
Shakespeare lived while Elizabeth I was the queen, she was part of the Tudor family. Richard II was of the Plantagenet family. These two families had a serious rivalry between each other so during Shakespeare's time the Plantagenets were perceived as evil. Shakespeare probably kept that image of Richard II to be politically correct. And through analysis of historical sources it seems that the potrayal of the king's personality differs significatively from the real king as he was not documented as so easy to surrender
