The Hunter's River Steam Navigation Company, started in the early 1840s, is recognised as the "tangible point of origin" of the Australasian United Steam Navigation Company (A.U.S.N.), although it had been preceded during the previous decade by a number of small joint-stock companies, intent on developing Newcastle-Sydney maritime trade.

After a further evolutionary ten years, which included difficult national economic times, the Hunter's River Steam business was taken over in 1851 by A.U.S.N., based in Sydney. Through good and bad times over the next century and more, the Company shared with pride, hard work and professionalism the maritime and infrastructure development of the Australian nation.

Through the Company's hands passed scores of ships, of wide-ranging types, size and trades, bulk and general. The fleet as the Second World War opened comprised fourteen ships:-

Typically, ships were requisitioned or closely controlled in their operations by the Commonwealth Government and its Defence arms, customarily fitted with at least defensive wartime equipment, and in a number of cases new voyages on this basis were commenced in July 1941. Three ships suffered at enemy hands, including two sunk.

For companies such as A.U.S.N. the succeeding years were turbulent, as they strained to meet the demands of the war effort and at the same time support the ongoing life of the nation at home in ways such as meeting the requirement to lift the annual sugar harvests' thousands of tons from northern ports to the population centres south. The Company also undertook management for some of the war years, of several ships which had escaped from Asia ahead of the Japanese invasion.

Bingera was taken up by the Navy for their purposes as early as 1 December 1939. Bulimba, of similar size, went under the control of the United States Small Ships Command during 1942, and though released from this in 1946, did not rejoin the Company's fleet. Following her requisition in May 1942, Baralaba, camouflaged and fitted for a special voyage - still a mystery - was returned to her owners in February 1943.

Before Australia was yet at war with Japan, Mareeba became a victim of the the German commerce raider vessel "Kormoran", while on a voyage, requisitioned, between Asian ports. Having sailed north from Fremantle on 13 May 1941, she was caught by the raider and sunk on 26 June, while en route Java-Colombo.

Macumba, participating in the supply and maintenance programme for the armed forces holding Australia's north, was en route Brisbane-Darwin when attacked and sunk by Japanese aircraft on 6 August 1943, one of the many victims on the coast that year. The Company's higher-profile Ormiston was torpedoed off Coffs Harbour that year also: having undertaken periodic war-oriented voyages from 1940 to 1942, including in 1940 trooping to Darwin and in December 1941 taking a Main Roads Department airfield construction team to Noumea, she had spent much time sustaining the Australian coastal service. Off the New South Wales coast on 12 May 1943, she suffered major hull damage from a Japanese submarine's torpedo. Temporary repairs at Coffs Harbour were followed by a slow voyage to Sydney. Repairs completed early in 1944, she trooped on the coast until July 1946 and hand-back to Owners.