The King had now to meet a more formidable combination of enemies than he had yet encountered. Henry Percy, eldest son of the Earl of Northumberland, the Harry Hotspur of Shakespeare, had been a trusted lieutenant of Henry. He had served in Wales against Glendower, and had been employed both in negotiations with the Scotch and in military action against them. He conceived himself to have been unjustly treated, for reasons which do not concern our present purpose, and to avenge his wrongs he formed an alliance with Owen Glendower and with the Earl of Douglas on behalf of the King of Scotland. Glendower was to invade Gloucestershire. To meet this danger the King issued briefs, under date of June 16th, to the Lieutenants of Gloucestershire, Shropshire, Worcestershire, and Herefordshire, directing that all persons liable to serve should put themselves at the command of his son, Henry, Prince of Wales. At the same time an attack on the northern borders was threatened from Scotland, and the Percies, whose disaffection was not yet known at Court, were commissioned to repel it. The King himself marched northwards to assist them, and seems to have been ignorant as late as July 10th of their real intentions. These, however, became known to him a day or so after, for he issued briefs to the Lieutenants of the counties, dated from Burton-on-Trent on July 16th, Lichfield on the 17th, and Westminster on the 18th, requiring military assistance to repel the invasion of Henry Percy with the Welsh rebels and “certain enemies of ours from Scotland” in his company. Six days later than the date of the Westminster brief the battle of Shrewsbury was fought. Prince Henry was on the field and bore himself bravely, though we must not credit him with the great achievement which Shakespeare attributes to him, of having slain Henry Percy in single combat. A lad, still wanting some months of sixteen, could hardly have vanquished a man of thirty, one of the bravest and most expert soldiers of his time. Hotspur seems to have been killed by a chance arrow as he was charging with characteristic impetuosity the royal forces. The young Prince was himself wounded in the forehead by an arrow. His father’s confidence in him was continued. Two days after the battle he expresses his trust in the loyalty and prudent caution of his son, Henry, Prince of Wales, and gives him full power to amnesty at his discretion such persons concerned in the late rebellion as he might think fit, in the county of Chester and in other places named.