Question: What is the date of death of Edmund Of Langley, 1St Duke Of York's father?
Sentence (from "Edmund of Langley, 1st Duke of York"): He was the founder of the House of York, but it was through the marriage of his younger son, Richard of Conisburgh, 3rd Earl of Cambridge, to Anne de Mortimer, great-granddaughter of Edmund's elder brother Lionel of Antwerp, 1st Duke of Clarence, that the House of York made its claim to the English throne in the Wars of the Roses.
Relevant evidence: No