 The Barracks housed the Department of Defence from the creation of the Commonwealth of Australia (Federation) in 1901 until 1958 when the Department of Defence moved to the new Russell Offices in Canberra.The earliest building (G Block) at Victoria Barracks was built by soldiers on the 40th Regiment, under the supervision of a Royal Engineer officer, from 1856 to 1858, while the remaining buildings were built by civil contractors with the original bluestone buildings being constructed between 1856 and 1872.A large extension (A Block New Wing) was added to accommodate HQ Department of Defence in 1917 and while it looked like the original A Block building the construction method and interior was completely modern for the time.