Richard of Cornwall (5 January 1209 - 2 April 1272), Comte de Poitou (before 1225), Count of Cornwall (1227) and King of the Romans (1257), was the second son of King John "Lackland and, thus, the younger brother of King Henry III; although all other mediaeval lords of Cornwall have been known as "Earl" (or, later, "Duke"), as he is most known to history through continental accounts his version of that title has come down to us in a French-derived rendering.
He married, firstly, 30 March 1231, Isabel Marshal, widow of Gilbert de Clare, Earl of Gloucester and Hertford, and daughter of William Marshal, 1st Earl of Pembroke. She died in childbed 17 January 1240.
He had four children by his first wife and two sons by second wife, but none of these had children; his only descendants are via his illegitimate son (Richard de Cornwall) by Joan de Vautort (or Valletort).
He was buried at Hayles Abbey, which he had founded.