The barracks were completed just before the Irish Rebellion in 1798. In 1873 a system of recruiting areas based on counties was instituted under the Cardwell Reforms and the barracks became the depot for the 83rd (County of Dublin) Regiment of Foot and the 86th (Royal County Down) Regiment of Foot. Following the Childers Reforms, the 83rd and 86th regiments amalgamated to form the Royal Irish Rifles with its depot in the barracks in 1881. A major extension was built between 1880 and 1881 to accommodate the extra troops.