From 1297 to 1314 he was in effect the king's continual commissioner of array in North Wales: he repeatedly raised contingents of Welshmen for service in Flanders or Scotland, and himself served in both those theatres of war. He was the first Welshman to be extensively employed as sheriff in North Wales, in Caernarvonshire 1301-5, in Anglesey 1305-6, again in Caernarvonshire 1308-10, and in Merionethshire 1314-16 and again 1321-7. He was also forester of North Wales 1307-17. Edward of Caernarvon, both as prince and as king, put great trust in him. When in 1321, in one of the recurrent crises of his reign, Edward found himself faced by a hostile coalition of Marcher barons led by Roger de Mortimer of Chirk, (q.v.), then justice of Wales, he ordered Gruffydd Llwyd to raise troops in North Wales and link up with the king's suppressing any rebels on his way. Accordingly, in Jan. 1322, Gruffydd attacked and captured a number of castles, including Holt, Welshpool and Mortimer's stronghold of Chirk, whereupon the Mortimers submitted to Edward without further resistance. It was this campaign of Gruffydd's that came to be traditionally misunderstood as a revolt against the king's officers in Wales: in reality, Gruffydd acted in the closest concert with the king, and by capturing Chirk did him a crowning service. He remained a consistent partisan of Edward II to the end: in 1327 he evaded appearing as one of the Merionethshire representatives in the Parliament which saw the final formalities of the king's overthrow, and one of the last references to him in the records shows him in 1331 associated with persons who had evidently favoured the execution of Edward's old enemy Mortimer in the previous year.
Sir Gruffydd Llwyd d. shortly before 12 July 1335. His heir was his son Ieuan, and he also had (according to Welsh pedigrees) seven daughters of his marriage with Gwenllian, daughter of Cynan ap Maredudd.
Professor Sir John Goronwy Edwards, D.Litt., F.B.A., F.S.A., (1891-1976), London