thdrew to the Welsh
Marches, refusing to own Henry for king. The danger was averted by the
luck which threw Sir Edmund as a captive into the hands of Owen Glyndwr in
the battle of Brynglas. It was natural that Henry should refuse to allow
Mortimer's kinsmen to ransom so formidable an enemy; but among these
kinsmen Henry Percy ranked himself through his marriage with Sir Edmund's
sister, and the refusal served as a pretext for a final breach with the
king.

[Sidenote: Overthrow of the Percies]

Percy had withdrawn from the Welsh war in wrath at the inadequate support
which Henry gave him; and his anger had been increased by a delay in
repayment of the sums spent by his house in the contest with Scotland, as
well as by the king's demand that he should surrender the Earl of Douglas
whom he had taken prisoner at Homildon Hill. He now became the centre of a
great conspiracy to place the Earl of March upon the throne. His father,
the Earl of Northumberland, his uncle, Thomas Percy, the Earl of
Worcester, joined in the plot. Sir Edmund Mortimer negotiated for aid from
Owen Glyndwr; the Earl of Douglas threw in his fortunes with the
confederates; and Henry Percy himself crossed to France and obtained
promises of support. The war party had now gained the upper hand at the
French court; in 1403 preparations were made to attack Calais, and a
Breton fleet put to sea. At the news of its presence in the Channel Henry
Percy and the Earl of Worcester at once rose in the north and struck
across England to join Owen Glyndwr in Wales, while the Earl of
Northumberland gathered a second army and advanced more slowly to their
support. But Glyndwr was still busy with the siege of Caermarthen, and the
king by a hasty march flung himself across the road of the Percies as they
reached Shrewsbury. On the twenty-third of July a fierce fight ended in
the defeat of the rebel force. Henry Percy was slain in battle, the Earl
of Worcester taken and beheaded; while Northumberland, who had been
delayed by an army under his rival in the north, Neville, Earl of
Westmoreland, was thrown into prison, and only pardoned on his
protestations of innocence. The quick, hard blow did its work. The young
Earl of March betrayed the plans of his partizans to purchase pardon. The
Breton fleet, which had defeated an English fleet in the Channel and made
a descent upon Plymouth, withdrew to its harbours; and though the Duke of
Burgundy was on the point of commencing t