The Earl was disgusted and indignant at the ingratitude of Henry. It was by his aid that Henry had advanced to the throne. Henry had conferred upon him some gifts in return, but Northumberland was not easily satisfied. Henry, on the one hand, was jealous of the power which had seated him on the throne; and the earl, on the other, was discontented with the compensation which Henry had made. The interference of the king with the right of Northumberland to dispose of his prisoners according to his own wish was deemed a fresh insult and injury. Northumberland determined upon revenge by overturning the throne which had been established principally by him. To this end he and his adherents proclaimed that Richard was alive, but that having been satisfactorily disproved, he planned a scheme for defending the claim of Mortimer to the crown. It was laid that the armies of Wales and Scotland should be united. Mortimer entered into covenant with Northumberland to bring an army into the Marches, which the Welsh, commanded by Glendower, were to join. The Earl of Worcester, brother of Northumberland, joined the forces, and in order to win over the Scots to the compact, Douglas and the other prisoners were set at liberty. At the moment when everything was ready for an engagement Northumberland was suddenly seized with a dangerous malady at Berwick. The conduct of the army was taken by his son Percy, surnamed Hotspur, this “Mars in swaddling clothes,” “this infant warrior,” who _Doth fill fields with harness in the realm_ _Turns head against the lion’s armed jaws_, _Leads ancient lords and reverend bishops on_ _To bloody battles and to bruising arms_.