As the Penal Laws in existence in Restoration Ireland made it very difficult for Catholics to serve in the Irish Army he instead joined the British Brigade serving in the Portuguese Restoration War between 1662 and 1668.
He then transferred into the French Army, serving with Thomas Dongan's Irish Regiment which had been formed by Charles II to fight for his ally Louis XIV of France.
[1] During the reign of James II, he was one of a group of experienced Irish Catholic officers given commands when the Irish Army was purged of its Protestant members by the new Lord Deputy of Ireland the Earl of Tyrconnell.
He and his colleagues were given the task of professionalising the large number of new Catholic recruits, particularly during the Curragh camps of 1686 and 1687.
He was fatally wounded during an engagement at the Moyry Pass on 22 June 1690 during the run-up to the Battle of the Boyne campaign.