HMAS Sydney was one of the three modified Leander class Royal Navy light cruisers sold to the Royal Australian Navy prior to her 1934 launch.
Seeing operational service in the Abyssinian crisis HMAS Sydney was assigned to escort and patrol duties in Australian waters at the start of Wold War 2 before joining the Mediterranean Fleet for an eight-month deployment, during which time she sank two Italian warships, participated in multiple shore bombardments, and provided support for Malta Convoys.
Returning to Australia in February 1941 HMAS Sydney resumed escort and patrol duties until investigating a suspicious merchant vessel on the 17th of November. Closing perhaps unwisely before receiving the correct response to her challenge HMAS Sydney was engaged at close range by the German merchant raider Kormoran, allowing her much smaller guns to inflict penetration and fire damage which would result in the loss of the cruiser with all hands. While Sydney's main guns were unable to depress to fire at such a close target the cruisers secondary armament ensured the armed merchant ship would sink, though slowly enough for the German crew to abandon ship in an orderly manner.
The wrecks of both HMAS Sydney and the Kormoran were found in March 2008 and both wrecks have been placed on the Australian National Heritage register.