He was born in about 1498, the first and only surviving son and heir of William Courtenay, 1st Earl of Devon (1475–1511) by his wife Princess Catherine of York (died 1527), the sixth daughter of King Edward IV by his wife Elizabeth Woodville.Burke, Bernard. Burke's Genealogical and Heraldic History of Peerage, Baronetage and Knightage, London; Harrison and Sons, 1914, p. 618 His maternal first cousins therefore included King Henry VIII.
