The Scottish-built vessel was launched in 1924 as a combination passenger liner and refrigerated cargo ship and operated a trade route between Western Australia and Singapore via the Dutch East Indies (now Indonesia), carrying passengers, cargo, and livestock. At the start of World War II, "Centaur" (like all British Merchant Navy vessels) was placed under British Admiralty control, but after being fitted with defensive equipment, was allowed to continue normal operations. In November 1941, the ship rescued German survivors of the engagement between "Kormoran" and HMAS "Sydney". "Centaur" was relocated to Australia's east coast in October 1942, and used to transport materiel to New Guinea.