Dictionary of National Biography, 1885-1900/Douglas, William (1398?-1437)
DOUGLAS, WILLIAM, second Earl of Angus (1398?–1437), was the elder son of George, first earl [q. v.], and Mary Stuart, daughter of Robert III, and succeeded to the earldom on his father's death of the plague in England, where he had remained as a prisoner after his capture at Homildon in 1402. The exact date of his accession to the earldom has not been ascertained. In 1410 he was betrothed to his future wife, Margaret, daughter of Sir W. Hay of Yester, but the marriage does not seem to have taken place till 1425, when a dispensation was obtained from the pope. He was named as one of the hostages to the English king when James I was allowed to return from his captivity in 1424, but he does not appear in the final list, and when James came to Durham he met and accompanied him to Scotland, and received the honour of knighthood. He is said to have been one of the nobles arrested along with Albany and his sons in 1425, but if so he was at once released, for he sat on the assize at Albany's trial. He took part in the king's highland expedition, and had Alexander, the Lord of the Isles, committed to his custody at Tantallon in 1429. In 1430 he was sent on an embassy to England, and three years after he was appointed warden of the middle marches.
When Henry Percy threatened to invade Scotland in 1435, Angus was sent to oppose him, and defeated an English force under Sir Robert Ogle at Piperden on 30 Sept. He died in 1437, leaving a son, James, third earl of Angus, who held the title till 1452, when he died and was succeeded by his uncle, George, fourth earl of Angus and Lord of Douglas [q. v.] He had married Joanna, a daughter of James I, but they had no children, and on his death she married James, earl of Morton. The only event recorded of this earl is the submission to him of Robert Fleming of Cumbernauld, a follower of the Earls of Douglas, who had burnt the corn on his lands of North Berwick, and in order to avoid retaliation entered into a bond for two thousand merks to surrender himself at Tantallon or the Hermitage on eight days' warning. In this bond, dated 24 Sept. 1444, the third earl is designated Earl of Angus, lord of Liddesdale and Jedward Forest. The occasion of its being granted is a sign, as Hume of Godscroft notes, that there was already rivalry between the Earls of Angus and their kinsmen, the Earls of Douglas.
[Fordun's Chronicle; the family histories of Hume of Godscroft and Sir W. Fraser.]