Dictionary of National Biography, 1885-1900/Mar, Donald (1293?-1332)
MAR, DONALD, twelfth Earl of (1293?–1332), was the son of Gratney, eleventh earl, and Lady Christian Bruce, sister of King Robert Bruce. He was probably born about 1293 (Fraser, Red Book of Menteith, vol. i. p. lxxx), and, as his father died about 1305, he was but a young boy at the time of his succession. After the defeat of Bruce at Methven in 1306, along with others, Mar was brought to Edward in token of submission, and was carried prisoner to England, where, in respect of his tender age, he was entrusted to the custody of the Bishop of Chester, first in the castle of Bristol, and afterwards at the bishop's own house, with suitable attendants (Palgrave, Documents and Records, Scotland, pp. 353-6). He spent nearly all the remainder of his life in England, taking service with Edward III, for which he received fifteen pence per day as wages. During this time he is never styled earl, but simply Donald of Mar. He was the owner of a trading vessel there called La Blithe.
After the battle of Bannockburn, in 1314, Mar and his mother, with Bruce's wife and daughter, and Wishart, bishop of Glasgow, were exchanged for the Earl of Hereford, Edward's brother-in-law, who had been taken prisoner by the Scots at Both well. But when Newcastle was reached in their journey to Scotland Mar turned back, preferring to remain in England (Chronicon dc Lanercost, p. 229). He paid visits to Scotland in 1318 and 1323. But to encourage him to remain in his service Edward conferred upon him various grants of lands and wardships, including the manor of Longbynington in Lincolnshire, and in 1321 appointed him keeper of Newark Castle (some call it Bristol Castle), which he held for the king till 1326, when he delivered it up to Queen Isabella and Lord Mortimer (Scalacronica, p. 151). He went to Scotland in 1327 for assistance to replace Edward III upon his throne, but instead of bringing help he joined the Scots in their raid of that year to Byland Abbey in Yorkshire, and was declared a rebel by Edward. Mar now remained in Scotland, and assumed his position as one of the seven earls. He had grants of lands from Bruce there in 1328 and 1329, and after the death of Randolph, 30 July 1332, he was chosen regent of Scotland. But he only held the honour ten days. Edward Baliol landed in Scotland the very day of his appointment, and Mar took command of the Scottish force which was raised to meet him, a post for which he was no way qualified. The battle was fought on 9 Aug. at Dupplin Moor in Perthshire, and Mar's army of thirty thousand was routed by Baliol's of three thousand, and himself slain. He left a widow, Isobel Stewart, who had two other husbands, Geofrey de Moubray, whom she divorced, and Sir William Carswell; also a son, Thomas, who succeeded as thirteenth earl of Mar [q. v.], and a daughter, Margaret, who succeeded as Countess of Mar after her brother's death, and married William, first earl of Douglas [q. v.]
[Bain's Calendar of Documents relating to Scotland, vol. iii. passim; Antiquities of Aberdeenshire (Spalding Club), iv. 698-725; Acts of the Parliaments of Scotland, i. 13-97.]