Jones and another officer, Colonel Drummond, accompanied
Lord Fauconberg (a son-in-law of the
Lord Protector Oliver Cromwell). Jones volunteered to join Sir
William Lockhart's Brigade which fought alongside the French army at the
siege of Dunkirk and at the
Battle of the Dunes on 4 June 1658. At the
Battle of the Dunes Jones was attached to
Lockhart's New Model Army regiment. The regiment was under the command of Lieutenant-Colonel
Roger Fenwick when it attacked veteran Spanish soldiers ensconced on top of dune (sand-hill). The sides of the dune were so steep that attacking English had to scramble up on hands and knees. The English, after two volleys and
push of pike, drove the Spanish from the crest of the dune and then pursued them down the far side. They were then in turn attacked by Anglo-Spanish cavalry who were unable to break the English formation and were themselves then driven off by French cavalry. By then all the regimental officers were either dead, or wounded. Jones himself had been, shot through the shoulder and wounded in two other places, but this did not deter him from seizing a loose French cavalry horse and joining the French cavalry in the counter-attack on the Anglo-Spanish cavalry. However, Jones pursued the enemy too far and was captured. Jones had displayed such valour in this action that on his release from a short captivity (he was part of a prisoner exchange), he was dubbed a knight bachelor by
Oliver Cromwell on 17 July 1658 (this honour, like all Protectorate honours, passed into oblivion at the
Restoration in May 1660), and was promoted to the lieutenant-colonelcy of
John Hewson's infantry regiment. ==Restoration==