Asimov: Henry V

p. 459: the legalistic justification for the first part of the Hundred Years' War -- Edward III's foray into France.

Henry V was now on the throne and eager to tak up once more the argument of Edward III.

Genealogy:
Edward III
fourth son, John of Gaunt / Blanche of Lancaster
Henry IV
Prince of Wales -- Prince Hal -- Henry V -- so Henry V was the great-grandson of Edward III

Henry V was eager to claim the throne as the French king despite the Salic Law.
inheritance of property; and,
inheritance of titles, and kings.

Now, p. 461: Edmund Mortimer, 5th Earl of March.

Hotspur (again): 

Sir Henry Percy KG (20 May 1364 – 21 July 1403), nicknamed Hotspur or Harry Hotspur, was an English knight who fought in several campaigns against the Scots in the northern border and against the French during the Hundred Years' War. 

The nickname "Hotspur" was given to him by the Scots as a tribute to his speed in advance and readiness to attack. The heir to a leading noble family in northern England, Hotspur was one of the earliest and prime movers behind the deposition of King Richard II in favour of Henry Bolingbroke in 1399. He later fell out with the new regime and rebelled, and was slain at the Battle of Shrewsbury in 1403 at the height of his fame.

Charles Neville, 6th Earl of Westmorland. Landowner; rebelled against Elizabeth I.

p. 464