"Upon Richard II.'s resignation ... Henry, Duke of Lancaster, having then a large army in the kingdom ... it was impossible for any other title to be asserted with safety, and he became king under the title of Henry IV. He was, nevertheless, not admitted to the crown until he had declared that he {121} claimed, not as a conqueror (which he was much inclined to do), but as a successor descended by right line of the blood royal.... And in order to this he set up a show of two titles: the one upon the pretence of being the first of the blood royal of the entire male line; whereas the Duke of Clarence (Lionel, elder brother of John of Gaunt) left only one daughter, Philippa: the other, by reviving an exploded rumour, first propagated by John of Gaunt, that Edmond Earl of Lancaster (to whom Henry's mother was heiress) was in reality the elder brother of King Edward I., though his parents, on account of his personal deformity, had imposed him on the world for the younger."--Blackstone's _Commentaries_, book i. ch. iii. p. 203. of edit. 1787. This Edmond, Earl of Lancaster, was succeeded by his son Thomas, who in the fifteenth year of the reign of Edward II. was attainted of high treason. In the first of Edward III. his attainder was reversed, and his son Henry inherited his titles, and subsequently was created Duke of Lancaster. Blanche, daughter of Henry, first Duke of Lancaster, subsequently became his heir, and was second wife to John of Gaunt, and mother to Henry IV. Edward IV.'s claim to the throne was by descent from Lionel, Duke of Clarence, third son of Edward III., his mother being Cicely, youngest daughter of Ralph Neville, Earl of Westmoreland. Lionel married Elizabeth de Burgh, an Irish heiress, who died shortly after, leaving one daughter, Philippa. As William of Hatfield, second son of Edward III., died at an early age, without issue, according to all our ideas of hereditary succession Philippa, only child of Edward III.'s third son, ought to have inherited before the son of his fourth son; and Sir Edward Coke expressly declares, that the right of the crown was in the descent from Philippa, daughter and heir of Lionel, Duke of Clarence. Henry IV.'s right, however, was incontestable, being based on overwhelming might. Philippa married Edward Mortimer, Earl of March. Roger, their son, succeeded his father in his titles, and left one daughter, Anne, who married Richard, Earl of Cambridge, son of Edmund Langley, Duke of York, which Edmund, Duke of York, was the fifth son of Edward III.; and thus the line of York, though a younger branch of the royal family, took precedence, _de jure_, of the Lancaster line. From this union sprang Richard, Duke of York, who was killed under the walls of Sandal Castle, and who left his titles and pretensions to Edward, afterwards the fourth king of that name.