2018 Land Sea Air Silver $5 Proof Triangular Coin

The Commonwealth Military Force and Commonwealth Naval Force were established in 1901 by amalgamating the state-based military forces that had previously existed in each of the states.

Both the Permanent Army and the Citizen Military Forces existed for home defence only, although the Australian Government established the Royal Australian Navy in 1911 for overseas service. At the outset of the First World War (and again during the Second World War) the Government raised the Australian Imperial Force exclusively for overseas service, basing its recruitment entirely on volunteers.

The Australian Flying Corps was established in 1912 and went on to become the Royal Australian Air Force in 1921.

The Australian Military Forces were reorganised following the Second World War. The Australian Regular Army was formed in 1947 and was supported by the reorganised Citizen Military Forces.

This branch of the Australian Defence Force subsequently went on to be officially called the Australian Army. Having previously operated independently from each other, in 1976, each of the three services were grouped under a single headquarters command known as the Australian Defence Force.