Soon after War was declared in August 1914, an internment camp for enemy aliens was set up on Rottnest Island. Enemy aliens were civilians living in Western Australia, who were citizens of Germany or countries of the Austro-Hungarian Empire, now at war with Australia, and thus considered a security threat. Rottnest Camp closed in November 1915 and most of the inmates were sent to a central internment camp at Liverpool on the outskirts of Sydney, New South Wales. From then to the end of the War, enemy aliens, arrested by the police, were taken to the Barracks for interview by an Army Intelligence officer. There they were detained until transported to Liverpool or released on parole into the community. Artillery Barracks was designated a “Concentration Camp”, a term used at that time for a guarded compound where non-combatant enemy civilians were held for security reasons. By 1917, there were at times over 50 prisoners held at the Barracks, most pending transport east. A few were retained at the Barracks to do “useful work”. Sylvester Sirch tended the horses, Edward Kilian was a gardener, Theodore Braun was a carpenter and William Unger and Walter Angliss were labourers. All of these men were later sent to Liverpool camp. On Christmas Eve 1915 an internee escaped from Artillery Barracks and was never found. In August 1917, three internees escaped and only two were recaptured. By November 1917, internees were required to wear a prison uniform. In response to their plea to be allowed to wear their own clothes, Major Griffiths, the CO of the Barracks responded “Owing to Prisoners of War breaking out of Barracks, I issued an order that all plain clothes were to be returned to store”. A few weeks later, in February 1918, two German prisoners, Francis Derschow and Robert Backer, escaped together, just days before they were due to be transported to NSW. After four days they were found by police detectives hiding in a boarding house in Stirling Street, Fremantle. The landlady, an Englishwoman who was known to have “German sympathies” was prosecuted for “knowingly harbouring prisoners of war” and sentenced to two months imprisonment. Both escapees were wearing civilian clothes when found.