After serving in Afghanistan and in the North-West Frontier Province, the regiment joined the Sindh Expedition, coming under the command of General Sir Charles James Napier, who conquered Sindh in 1843 and sent back to the Governor General the one-word message "Peccavi" – Latin for "I have sinned". At the Battle of Meeanee, a bond was cemented between Napier and the regiment, which sixty years later was given his name. Napier later wrote: "The 25th played a distinguished part in the engagement. Had the 22nd (The Queen's Regiment) and the 25th given way, all would have been lost."