The Chronicon Angliæ records that “Philippa regina Angliæ” gave birth 5 Jun “apud Langley juxta Sanctum Albanum” to “filium...Edmundus”, dated to 1341 from the context. Created Earl of Cambridge 13 Nov 1362. He served in the campaign in Brittany 1369, at the siege of Limoges Sep 1370. Created Duke of York 6 Aug 1385. Regent of England 29 Sep 1394-May 1395, 6 Aug 1395, and 27 Sep-Nov 1396, during the King's absences, and also in 1399 when his nephew Henry Duke of Lancaster landed, with whom he made peace.
Betrothed (19 Oct 1364) to Marguerite de Flandre, widow of Philippe I "de Rouvres" Duke of Burgundy, daughter of Louis III "de Mâle" Count of Flanders & his wife Marguerite de Brabant. This betrothal was arranged under the Treaty of Dover 19 Oct 1364, but the French persuaded Pope Urban V to refuse a dispensation on grounds of consanguinity. A charter dated 20 Jul 1364 records negotiations for the marriage between “nostre...cousin le conte de Flandres...Margarete duchesse de Burgoigne file au dit conte” and “nostre...filz Esmon de Langele”. The contract for the marriage between “Edward...roi Engleterre...messieur Esmon counte de Cantebrigg filz au dit roi” and “Loys counte de Flandres, duc de Brabant, counte de Nyvers et de Rechest et sire de Malynes...dame Margarete duchesse de Burgoigne sa fille”. The Chronicon Angliæ records the betrothal of “Edmundus de Langley filius regis Edwardi” and “filiam et heredem...comitis Flandriæ”, adding that “rex Franciæ Karolus” blocked the marriage, dated to 1364 from the context. 2
Edmund of Langley 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. The other party in the Wars of the Roses, the incumbent House of Lancaster, was formed from descendants of Edmund's elder brother John of Gaunt, 1st Duke of Lancaster, Edward III's third son. 3
Created earl of Cambridge in 1362 and duke of York in 1385, Edmund was the least able of Edward III’s sons, and in the political strife of Richard II’s reign he played an ineffective part. Between 1359 and 1378 he served without distinction in several campaigns in France, Spain, and Brittany, and his one independent command, the Lisbon expedition of 1381–82 to aid King Ferdinand of Portugal against Castile, was a failure. York was appointed keeper of the realm during Richard II’s absence in Ireland in 1394–95, and again on the King’s departure for his second Irish expedition in May 1399. When Henry of Lancaster (afterward King Henry IV) invaded England (July), York tried to organize resistance, but he soon submitted (July 27), recognizing that Richard’s cause was lost. 4
By his will, dated 25th November 1400, Edmund of Langley directed his interment in the Church of the Friary of Langley, near the remains of Isabel, his first consort, who had died in 1392. The tomb of alabaster and black marble, richly sculptured and adorned with shields of arms, was, at the dissolution of the Friary, removed into the north-east corner of the chancel of the parish church of Langley, where it is still extant.
"Shakespeare found Edmund in the chronicles in the shape of a man who loved hunting and good cheer and avoided the council chamber--just the kind of person, in fact, to provide a contrast in temperament with Richard II and in ability with Bolingbroke. York has no refinement of understanding and no political ambition. He is a sturdy, honest, well-meaning man, prompt with sensible advice but easily flustered, shrewd enough to see what's coming but not clever or resolute enough to prevent it. Normally he makes the best of a bad business--which is usually not so bad after all, either for himself or for the nation." 5