He accompanied the Earl of Essex in his military expedition of 1599–1600 to Ireland, and was knighted on 13 July 1599 for his gallantry in an action at Arklow. He was subsequently put in command of a brigade of cavalry, and he was credited with playing an important part in victory at the Siege of Kinsale on 24 December 1601, when his troops broke through the enemy line and captured the Spanish commander. For his services he was highly commended by the Crown, and made a member of the Privy Council of Ireland.