Permission to form the 2nd Battalion was given in July 1808. It was initially formed in Dublin, and in consequence its men were overwhelmingly Irish. Its first base was at Ashford in Kent. In July 1809 the Battalion was part of a huge force, numbering around 45000, put together to mount an attack on the ports and dockyards at the mouth of the Scheldt, including Antwerp and Flushing. The plan was ambitious, but it was not properly thought through and was implemented badly. Unable to achieve its intended landings, the force found itself on the island of Walcheren in the mouth of the Scheldt. The 2nd/11th was not involved in the limited fighting that took place on the island, and before a serious assault on Flushing could be mounted large numbers of the British soldiers fell ill with the fever that afflicted Walcheren every summer, a great many of whom died. The force withdrew in September.
After this inglorious episode, which became known as the Walcheren Campaign, the Battalion spent 9 months in England and a year in Guernsey and in early 1811 were posted to Gibraltar. Its light company spent some months helping in the defence of the British garrison in Tarifa, where they distinguished themselves in holding off French attacks. The whole Battalion spent about a year in 1813-14 in Ceuta. In March 1816 the order came for the Battalion’s disbandment, and when the 1st Battalion arrived in Gibraltar the 2nd was disbanded and amalgamated into the 1st.