GLENDOWER, or GLENDWR, OWEN (glen'diir), a Welsh chief ; born in Montgomeryshire about 1359. He was made esquire of the body to Richard II., and remained with him till his deposi tion by Henry IV. in 1399, after which he retired into private life. Shortly after the accession of the new king part )f Glendower's lands were seized by his neighbor, Lord Grey of Ruthin. There upon the Welshman, being unable to obtain redress from the English king, took up arms in his own cause, and in 1400 commenced operations by seizing the estates of Lord Grey. The king or dered his subjugation, and granted his estates to his brother, the Earl of Som erset. Then for two years Glendower carried on a guerrilla warfare against the English marches. In 1402 he drew Lord Grey into an ambush, and took him prisoner. In this same year Sir Edmund Mortimer, the uncle of the Earl of March, was also captured by Glendower.
Both Grey and Mortimer married daugh ters of the Welsh chieftain and with him formed the coalition with Harry Percy (Hotspur) against Henry of England. That coalition ended in the battle of Shrewsbury in July, 1403, in which the English king gained a decisive victory, Hotspur being among the slain. In June of the following year Glendower entered into a treaty with Charles VI. of France, who in 1405 sent a force to Wales to act against the English. Meantime, in the spring of 1405, Glendower had been twice severely defeated by Prince Henry of England. The Welsh prince neverthe less kept up a desultory warfare during the remaining years of his life. He never submitted to English rule, and is be lieved to have died peacefully in Mon mouthshire after 1416.