* August 1 – Edmund of Langley, 1st Duke of York, son of King Edward III of England ( b. 1341 )

* June 5 – Edmund of Langley, son of King Edward III of England ( d. 1402 )

** Edmund de Langley, 1st duke of York ( d. 1402 )

The other one was the York branch, initiated by his uncle Edmund of Langley, 1st Duke of York ( see section " Seniority in line from Edward III " below ).

:* Edmund of Langley, 1st Duke of York ( 1341 – 1402 )

Richard of York was not only the wealthiest magnate in the land, but was also descended from King Edward III's third son Lionel of Antwerp and fifth son Edmund of Langley, leading to calls that he be recognised as successor to the childless King Henry.

In the summer of 1370 John was sent with a small army to Aquitaine to reinforce his ailing elder brother, the Black Prince and his younger brother Edmund of Langley, Earl of Cambridge.

Thomas of Woodstock was named Duke of Gloucester and Edmund of Langley became Duke of York, thereby founding the House of York, which later fought for the throne with John of Gaunt's Lancastrian descendants during the Wars of the Roses.

After the manor came into the possession of Edward III he passed it to his son Edmund of Langley, 1st Duke of York, founder of the Yorkist line.

His paternal grandparents were Edmund of Langley, 1st Duke of York ( the fourth son of Edward III to survive infancy ) and Isabella of Castile.

With the dukedom of York, Richard inherited the associated arms of his ancestor, Edmund of Langley.

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.

Edmund of Langley had two sons, Edward, and Richard of Conisburgh.

| Edmund of Langley ( House of York founder ) 1385 – 1402 || Edmund of Langley || 5 June 1341Kings Langleyson of Edward III of England and Philippa of Hainault || Isabella of Castile13723 childrenJoan de Hollandca.

| Edward of Norwich1402 – 1415 || Edward of Norwich || 1373Norwichson of Edmund of Langley and Isabella of Castile || Philippa de Mohunc.

Edward of Norwich, Earl of Rutland, the first son of Edmund of Langley, 1st Duke of York, fifth son of Edward III of England, favorite of his cousin Richard II, had been created Earl of Cork in the Peerage of Ireland during his nephew's personal reign.

* Isabella ( 1355 – 1392 ), married Edmund of Langley

In 1363 Grantham Castle was granted to Edmund of Langley, 1st Duke of York, and fifth son of Edward III of England, It was north-east of St Wulfram's, and has its legacy in the naming of Castlegate.

After Conisbrough reverted to the Crown, Edward III gave it to his youngest son Edmund Langley and was probably during his tenure that the work to improve the accommodation in the inner ward was carried out.

The title Duke of York was first created in the Peerage of England in 1385 for Edmund of Langley, the fourth surviving son of Edward III, and an important character in Shakespeare's Richard II.

| Edmund of LangleyHouse of York 1385 – 1402 ' || Edmund of Langley || 5 June 1341Kings Langleyson of Edward III of England and Philippa of Hainault || Isabella of Castile13723 childrenJoan de Hollandno children ||

* Edmund Allenby, 1st Viscount Allenby, General ( later Field Marshal ), British Army

John Beaufort's granddaughter Lady Margaret Beaufort, a considerable heiress, was married to Edmund Tudor, 1st Earl of Richmond.

* May 14 – Edmund Allenby, 1st Viscount Allenby, British soldier and administrator ( b. 1861 )

** Edmund Allenby, 1st Viscount Allenby, British soldier and administrator ( d. 1936 )

* November 21 – Edmund Lyons, 1st Baron Lyons, British admiral ( d. 1858 )

* May 22 – Edmund Grey, 1st Earl of Kent ( b. 1416 )

* November 1 – Edmund Tudor, 1st Earl of Richmond, father of King Henry VII of England

* March – French troops under Guy de Richemont besiege the English commander in France, Edmund Beaufort, 1st Duke of Somerset, in Caen.

* October 26 – Edmund Grey, 1st Earl of Kent ( d. 1490 )

* August 5 – Edmund of Woodstock, 1st Earl of Kent, English politician ( d. 1330 )

* March 19 – Edmund of Woodstock, 1st Earl of Kent, son of Edward I and brother of Edward II, ( executed by Roger Mortimer ) ( b. 1301 )

* June 5 – Edmund Crouchback, 1st Earl of Lancaster, son of Henry III of England ( born 1245 )

* January 16 – Edmund Crouchback, 1st Earl of Lancaster, son of Henry III of England ( d. 1296 )

By the late 1440s, two opposing factions had formed behind Edmund Beaufort, 1st Duke of Somerset, and Richard of York.

His daughter Elizabeth de Badlesmere ( 1313 – 8 June 1356 ), was married firstly ( 27 June 1316 ) to Sir Edmund Mortimer ( 1302 – 17 December 1331 ), eldest son of Roger Mortimer, 1st Earl of March and Joan de Geneville, Baroness Geneville.

Even before the annulment of her first marriage, Henry VI chose Margaret as a suitable bride for his half-brother, Edmund Tudor, 1st Earl of Richmond.

Margaret Beaufort's arms as wife of Edmund Tudor, 1st Earl of Richmond | Edmund Tudor

Among their grievances was the King's failure to promptly pay the soldiers ' wages, his favour towards Dunbar, his demand that the Percies hand over their Scottish prisoners, his failure to put an end to Owain Glyn Dŵr's rebellion through a negotiated settlement, his increasing promotion of his son Prince Henry's military authority in Wales, and his failure to ransom the Percies ' kinsman, Henry Percy's brother-in-law, Sir Edmund Mortimer ( 1376 – 1409 ), whom the Welsh had captured in June 1402, and who had a claim to the crown as the grandson of Lionel, 1st Duke of Clarence, second surviving son of King Edward III.

Henry Percy married Elizabeth Mortimer, the eldest daughter of Edmund Mortimer, 3rd Earl of March, and his wife, Philippa, the only child of Lionel, 1st Duke of Clarence, and Elizabeth de Burgh, Countess of Ulster, and by her had two children:

:* Edmund Beaufort, 1st Duke of Somerset ( 1406-1455 )