Ashton was the son and heir of Sir Robert de Ashton, and it is remarkable that, although the chief recorded event of his life shows him to have been a man of conspicuous military courage, he does not appear to have received the honour of knighthood, or to have been employed in any of the offices in which his father had distinguished himself.
Whilst Edward III was fighting in France, David II of Scotland, entered Northumberland with a force estimated at 50,000 men, and wasted and pillaged the country as far as Durham. Queen Philippa, the heroic wife of Edward III, marched against the invaders with a force of about 12,000, whom she encouraged to the unequal conflict. Battle was joined at Neville"s Cross, near Durham, 17 October
1346, and the result was a decisive victory for the English.
Thomas de Ashton, who fought under Lord Neville, captured the royal standard of Scotland. Shortly after King David was made prisoner by John de Coupland, variously described as a Lancashire esquire and as a Northumberland gentleman, who was knighted when the king returned from France, but Ashton was still an esquire when, in 1385, he formed one of the retinue of John of Gaunt in his expedition to Spain.
