Her seven sister ships, also built in Australia, were Barcoo, Barwon, Burdekin, Gascoyne, Hawkesbury, Lachlan and Macquarie.
Diamantina was named after the Diamantina River in Queensland. The river was named after Countess Diamantina Roma Bowen, wife of the first Governor of Queensland, Sir George Ferguson Bowen.
She was built in Queensland by Walkers of Maryborough, was laid down 12 April, 1943 and launched on 06 April, 1944.
Diamantina served in New Guinea and Solomon Island waters during the latter part of World War 2 and the surrenders of Japanese forces at Nauru and Ocean Islands were signed on board.
DIAMANTINA - WAR SERVICE 1945
| 17 June: | Sydney - Cairns |
| 23 June: | Cairns - Madang, New Guinea |
| 27 June: | Langemak, New Guinea |
| 29 June: | Torokina, Bougainville |
| 01 July: | Freddy Beach |
| 06 July: | Freddy Beach and Saposa Island, Bougainville |
| 07 July: | Sohona Island, Bougainville - 1st Bombardment |
| 18 July: | Sohona Island, Bougainville - 2nd Bombardment |
| 19 July: | Radar Submarine Alarm |
| 19 July: | Sohona Island, Bougainville - 3rd Bombardment |
| 21 July: | Manus Island, Admiralty Group |
| 07 August: | Torokina, Bougainville |
| 09 August: | Sohona Island, Bougainville.- 4th Bombardment |
| 10 August: | Buka Passage, Bougainville & Choiseul Island, Solomons |
| 11 August: | Torokina, Bougainville |
| 14 August: | Lae, New Guinea |
| 14 August: | Langemak, New Guinea |
| 15 August: | Surrender Announced |
| 01 September: | Torokina, Bougainville |
| 08 September: | Bougainville - Japanese surrender |
| 13 September: | Nauru Island - Received Japanese Surrender |
| 19 September: | Torokina, Bougainville. |
| 26 September: | Tarawa, Gilbert Islands |
| 30 September: | Ocean Island - Received Japanese Surrender |
| 01 October: | Nauru Island |
| 06 October: | Torokina, Bougainville |
| 08 October: | Jacquinot Bay, New Britain |
| 10 October: | Madang, New Guinea |
| 29 October: | Emirau, Admiralty Group, Rabaul, Bougainville |
| 03 November: | Emirau, Admiralty Group |
| 06 November: | New Hanover, New Ireland |
| 10 November: | Rabaul, New Britain |
| 22 November: | Torokina, Bougainville |
| 25 November: | Dreger Harbour, New Guinea |
| 26 November: | Madang, New Guinea |
| 01 December: | Wewak, New Guinea |
She paid off to Reserve in August, 1948. After reconstruction she recommissioned on 22 June, 1959 as a Survey and Oceanographic Research vessel. One result of this work was the discovery, in 1961, of the deepest place in the Indian Ocean, off the coast of Western Australia. This sea trench is named the Diamantina Trench in her honour.
Diamantina acted as Escort Vessel for the Royal Yacht Britannia during the Queen's tour of Australia in March 1963.
Diamantina paid off in Sydney on 28 February, 1980 and was laid up pending disposal.
In September 1980, Diamantina was presented to the Queensland Maritime Museum and steamed to Brisbane in October of that year, being placed in the Dry Dock at South Brisbane.
Her significance to World War 2 maritime history is immense:
- She is one of only 2 surviving World War 2 veterans in the world upon which surrenders were signed
- She is the only survivor of a class of some 140 ships which saw extensive and successful service as convoy escorts in the Atlantic
- She is the largest World War 2 ship surviving in Australia
