Shrewsbury affected the position of Glendower and his English ally. The famous treaty of partition, which was perhaps signed in the house of the Archdeacon of Bangor on 28 Feb. 1405, was the work of Owen and his son-in-law (ib. ii. i. 27-8). In the threefold division of the kingdom which it proposed, Mortimer (his nephew's claims are now put on one side) was to have the whole of the south of England, though an engagement in which he resigned the marchland districts, in which his family was supreme, to Owen clearly bore the marks of coercion. But the whole question of the triple partition is a difficult and doubtful one. It plainly stands in close connection with the attempted abduction of the Earl of March in the same month and Northumberland's second rising (Ramsay, Lancaster and York, i. 86). But the failure of the general English attacks on Henry gradually reduced Glendower's revolt to its original character of a native Welsh rising against the English, and, from this point of view, Mortimer's help was much less necessary to him than from the standpoint of a general Eicardian attack on Henry of Lancaster. Mortimer therefore gradually sank into the background. After 1404 his father-in-law's cause began to lose ground, and Mortimer himself was soon reduced to great distress. He was finally besieged in Harlech Castle by the now victorious English, and perished miserably during the siege (Adam of Usk, p. 75). This was probably in the summer of 1409 (Tyler, Henry V, i. 230). Some of his strange adventures were commemorated in songs (Adam of Usk, p. 75). By Owen's daughter Mortimer had one son, named Lionel, and three daughters. She, with her family, was already in the hands of Henry V in June 1413, perhaps since the capture of Harlech, being kept in custody within the city of London (Devon, Issue Rolls of Exchequer, p. 321; Tyler, Henry V, i. 245). But before the end of the same year Lady Mortimer and her daughters were dead. They were buried at the expense of one pound within the church of St. Swithin's, London (Devon, p. 327).
[Ann. Hen. IV, apud Trokelowe (Rolls Ser.); Chron. Anal. ed. Giles; Monk of Evesham, ed. Hearne; Adam of Usk, ed. Thompson; Dugdale's Monasticon, vi. 355; Ellis's Original Letters, 2nd ser. vol. i.; Rymer's Fœdera; Ramsay's Lancaster and York; Wylie's Henry IV.]
MORTIMER, EDMUND (IV) de, Earl of March and Ulster (1391–1425), was the son of Roger de Mortimer (VI), fourth earl of March and Ulster [q. v.], and his wife Eleanor Holland, and was born in the New Forest on 6 Nov. 1391 (Monasticon, vi. 355). In his seventh year he succeeded, by the untimely death of his father in Ireland, to the titles and estates of the Mortimers. As Richard II had already recognised his father as heir-presumptive to the throne, the young earl himself was now looked upon by Richard's partisans as their future king. Next year (1399), however, the Lancastrian revolution and the fall of Richard entirely changed Edmund's position and prospects. He was now put under guard at Windsor on the pretext that he was the king's ward. His younger brother Roger also shared his captivity. The first parliament of Henry IV, by recognising the new king's son as heir-apparent, excluded March from all prospects of the throne. But though careful to prevent the enemies of Lancaster getting hold of his person, Henry showed proper regard both for the honour and interests of his ward. In 1401 March was recognised as a coheir of his great-aunt Philippa, countess of Pembroke, and in 1409 as one of the coheirs of his uncle Edmund Holland, earl of Kent (Dugdale, Baronage, i. 151). He remained in the king's custody (Adam of Usk, p. 61). On 5 July 1402 he was put under the care of Sir Hugh Waterton at Berkhampstead Castle, along with the king's children, John and Philippa, and his own brother, Roger (Fœdera, viii. 268). The fact that his aunt was the wife of Hotspur was in itself sufficient to secure for him honourable treatment during Henry IV's early years.
But the constant revolts of the Ricardian partisans, the defection of the Percies, and, above all, the association of his uncle, Sir Edmund Mortimer [q. v.], with Owen Glendower, made the safe custody of the Ricardian pretender essential to the security of the Lancastrian dynasty, especially after it became an avowed object of Glendower and his English associates to make the Earl of March king of England. Early in 1405 March and his brother were at Windsor, when on the early morning of 13 Feb. a bold attempt was made to carry them off to join Glendower and their uncle in Wales. A blacksmith was bribed to make false keys (Walsingham, Ypodigma Neustriæ, p. 412), and the children were successfully removed from the castle. They were, however, very soon recaptured, and Lady le Despenser, the daughter of Edmund of Langley, and the mistress of Edmund, earl of Kent, uncle of the two boys, was on 17 Feb. brought before the council charged with the offence (Ann. Hen. IV, p. 398; cf. Ramsay, Lancaster and York, i. 83-4). The question of the safe custody of the young Mortimers was brought before the