The House of York was a cadet branch of the English royal House of Plantagenet. Three of its members became Kings of England in the late 15th century. The House of York was descended in the male line from Edmund of Langley, 1st Duke of York, the fourth surviving son of Edward III, but also represented Edward's senior line, being cognatic descendants of Lionel, Duke of Clarence, Edward III's second surviving son. It is based on these descents that they claimed the English crown. Compared with the House of Lancaster, it had a senior claim to the throne of England according to cognatic primogeniture but junior claim according to the agnatic primogeniture.
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