Who was Richard Plantagenet?

Actually, there are a few answers to that question.

The first Richard Plantagenet was the 3rd Duke of York. He was the first member of the family to claim the Plantagenet surname in 1460. He was killed in conflicts with the house of Lancaster, but his sons Edward and Richard, both became English kings.

Before his son, Richard, became Richard III, he was known as Richard of Gloucester, not Richard Plantagenet.

Years after Richard's defeat at the Battle of Bosworth, another man called himself Richard Plantagenet. Also known as Richard of Eastwell, stories suggest that this man was Richard III's "natural" son.