Caernarfonshire militia was raised in 1762 under the 1757 act. It was an auxiliary force for the defence of the realm, independent of the standing army. At one point it was 900 strong and had barracks in Llaneris road and also an orderly room at 7 church street in 1793. It was deployed to the south coast to counter the French invasion in 1798 it left Fareham barracks for Ireland in 1813 to the end of the war, It also served in Scotland. It was disembodied in 1820 but served as a volunteer corps until after 1859.