Hugh can be traced soldiering in Scotland every year from 1335 to 1338. In July 1338, Hugh sailed from
Orwell with the king's army to
Antwerp in the
Duchy of Brabant. He took part in the
naval campaign in the English Channel and was present at the
battle of Sluys on 24 June 1340. In 1342–43, he served in the
comitiva (retinue) of the Earl of Pembroke during the
Breton campaign. He was serving under the Earl of Pembroke again during the
Aquitanian campaign of 1345, under the ultimate leadership of the Earl of Derby. According to the French chronicler
Jean Froissart, Hugh was present for Derby's victory in the
battle of Auberoche on 21 October 1345. It is known, however, that the Earl of Pembroke missed the battle and so it is possible that Froissart is mistaken in placing Hugh there. Hugh appears to have returned to England before the
Siege of Aiguillon, which lasted from April to August 1346 and resulted in England retaining control of the castle. The highest military post in which Hugh served was that of king's captain and lieutenant in
Flanders, to which he was appointed on 20 June 1346. In his capacity as Edward's Flemish lieutenant he mounted an attack on France's northern border as a diversion during the king's invasion of
Normandy in July. Hugh recruited an army from the Flemish towns and with his own retinue of 250, mostly archers, laid siege to
Béthune. His Flemish army proved undisciplined and the siege was abandoned in failure before the end of August. Hugh missed the great English victory at the
battle of Crécy on 26 August 1346, but with the lifting of the Béthune siege he joined the
siege of Calais, begun on 4 September, with his men-at-arms and some archers. He was still in the siege camp when he was appointed seneschal of Gascony in May 1347. ==Death and burial==