William Hunt, Dictionary of National Biography… (1895)
“ The Percys rose in revolt. Henry Percy had special grievances against the king, in which his father had some share. Northumberland was thwarted by the king's inability to supply him with the money that he needed for the war with the Scots, he had been treated somewhat shabbily with respect to the Scottish prisoners, he had good reason to suspect the king of endeavouring to represent him and his family as the cause of the poverty of the realm, and he was probably also jealous of the Earl of Westmorland, the earl's nephew by his first wife and the head of the rival house of the Nevilles of Raby. ”
