He took command in Ireland in the spring of 1691, and established his headquarters at Mullingar. Among those who held a command under him was the Marquis of Ruvigny, the recognized chief of the Huguenot refugees. Early in June, Ginkell took the fortress of Ballymore, capturing the whole garrison of 1,000 men. The English lost only eight men. After reconstructing the fortifications of Ballymore, the army marched to Athlone, then one of the most important of the fortified towns of Ireland and key to the Jacobite defensive position, as it bridged the River Shannon. The Irish defenders of the place were commanded by a distinguished French general, the Marquis de St Ruth. The firing began on 19 June, and on 30 June the town was stormed, the Irish army retreating towards Galway, and took up their next defensive position at Aughrim. Having strengthened the fortifications of Athlone and having left a garrison there, Ginkell led the English combined forces, on 8 July, westward in pursuit of the retreating army and met the Franco-Irish in formal battle on 12 July 1691 at Aughrim.