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Rottnest Island

Military history of Rottnest Island

Rottnest Island has played a military role in both World War I and World War II and has also had post-war training functions, which are described below. If you enjoy Rottnest Island Military History, why not take one of our Guided Tours?

World War I

With the start of World War I the Department of Defence commandeered the Island for use as an internment and Prisoner of War camp from 1914 to the end of 1915. In September 1915, the camp held 989 persons, including 841 Austrian and German internees and 148 Prisoners of War. Recreational and holiday pursuits were re-established in December 1915.

Preparation for World War II

In response to increasing global tensions in the 1930s, the Australian government developed a three-year Defence Development Program that it commenced in 1933. In the Plan, Rottnest Island was identified as being critical to the defence of Fremantle as guns there could engage hostile ships well before they approached the range that would allow bombardment of Fremantle Port.

In 1934 the Western Australian Premier officially informed the Rottnest Island Board of Control of the Commonwealth's intentions for a defence program on Rottnest Island and in 1936 it purchased land at Bickley for this purpose and construction began later that year.

The fixtures on Rottnest Island were made up of the Oliver Hill Battery with two 9.2-inch guns and quarters at Oliver Hill; Bickley Battery with two 6-inch guns and quarters at Bickley; permanent Army Barracks at Kingstown (containing living accommodation for four warrant officers or sergeants and 72 rank and file personnel, cottages for commanders, officers mess, cottages for married non-commissioned officers (NCOs) and gunners, Army institutional buildings, small hospital, dry canteen, workshop, store, railway buildings, and supporting communication and observation structures); a three storey fortress and battery command post building at Signal Ridge; Port War Signal Station at Signal Ridge; observation posts and engine rooms.

Also constructed by the military at this time were six searchlight emplacements, magazine shell stores, powerhouse, directing station and a railway from the jetty to the 9.2 inch guns. Improvements to the jetty were also undertaken. When the Barracks was completed in September 1937 Rottnest Island was declared a permanent station for troops.

World War II

In June 1940 the Island was declared a prohibited area and all recreational activity ended. The declaration was intended to last for three months, but continued for five years until June 1945. During the war period, administrative fire command staff and a coastal artillery gunnery school occupied Rottnest Island. The guns were manned 24 hours a day.

In the mid-1940s, the focus of threat moved to Northern Australia, so the fixed defences at Rottnest Island were reduced. The 9.2-inch guns were put on a maintenance basis and only the 6-inch guns at Bickley remained manned. The period of intensive military activity on Rottnest Island ended with the guns never being fired at the enemy.

Post war

After the war, all military units were disbanded and the guns placed in long term storage. By April 1945 all Thomson Bay buildings had been vacated by the military with the exception of the bakehouse and garage. Approximately 200 Italian internees were sent to the Island for four months to carry out repairs and renovations.

In June 1945, the prohibition order on Rottnest Island was lifted but until October only people travelling on commercial vessels could visit the Island. Dismantling of the battery was finalised in March 1953. An artillery maintenance detachment remained on the Island until 1960.

In 1953, the Army decided that further use for Kingstown Barracks was no longer necessary. This changed in early 1955 when it was determined the Barracks would continue to be used for training purposes. Training at Kingstown Barracks recommenced in May 1955.

In 1962 it was determined that the use of coastal artillery in the defence of ports was out-moded and coastal artillery guns and ammunitions around the nation were declared for disposal. The 9.2-inch battery on Rottnest Island was saved from disposal because the high cost of removing and shipping the guns to the mainland exceeded their value as scrap metal.

In 1967, the Army returned most of its land holdings on Rottnest Island to the Western Australian Government, retaining Kingstown Barracks, the Bickley area and easements necessary to connect water to the Barracks. The Army's use of Kingstown Barracks declined gradually from the 1960s to the 1970s and then sharply from 1974, to the point in 1979 where it was utilised for only 43 days in the year. In 1984 the Army and the Rottnest Island Board of Control began negotiations for the Board to purchase the remaining Army land and buildings including Kingstown Barracks. This was formalised in an official closing ceremony in December 1984.

After successful trials using Kingstown Barracks for environmental education programs over the 1984/1985 summer season, the Board recommended to the Government that the Barracks be used as an environmental education centre.

Engineering Heritage National Landmark Award

Engineering Heritage Australia’s highest accolade, an Engineering Heritage National Landmark award, was presented to the Rottnest Island Authority on 10 November 2010. 

The award recognises the significant technical achievement of the construction of the Fremantle Fortress – Rottnest Island World War II Coastal Defences Facilities. A video was produced by one of the nominating Engineers, Mark Bush. View the video above. 

In 2013, Rottnest Island celebrated the 75th anniversary of Rottnest Island’s 9.2-inch guns being made “action ready” as part of Fremantle Fortress – WWII coastal defences.