He served at the Siege of Barcelona in 1714 alongside Berwick, and was wounded in the final assault. In 1718 he was involved in a Jacobite plan to launch a rebellion and place James on the throne of Britain and Ireland. Sarsfield travelled to Ireland, but a series of military defeats in Scotland and at sea led to the withdrawal of the Jacobite plotters in May 1719. Shortly after arriving at St Omer he died.