When Henry V of England ascended to the throne in 1415, Sir Hugh's popularity increased. He traveled to France with the English army, to re-incite the 100 Years' War. He proved to be a daring leader, and was one of the key commanders at the Siege of Harfleur, and at the Siege of Rouen. After the siege, he returned home to England, and in 1417, he entered the service of Henry V, becoming one of his most loyal retainers. Throughout the rest of his life, he would have a splendid relationship with the king.