Cap badge 19th Inf bat The South Sidney Regiment 1927-1942

In 1927, the unit adopted the territorial designation of "The South Sydney Regiment".At the same time the motto Fortiter et Fideliter (Boldly and Faithfully) was authorised.The battalion was assigned to the 9th Brigade, 2nd Division, upon its re-establishment.Initially, the Citizens Force was maintained through a system of compulsory service, however, in 1929–30, after the election of the Scullin Labor government, the Citizens Force was reorganised as the "Militia", and was maintained on a volunteer only basis. Throughout the 1930s, as a result of manpower shortages and the austerity measures that resulted from the economic hardships of the Great Depression, the unit was amalgamated with the 1st Battalion. In 1939, these two battalions were delinked, however, the 19th was further amalgamated with the 20th Battalion to form the 20th/19th Battalion, adopting the territorial designation of the "Parramatta and Blue Mountains Regiment"