The Undanbi were an indigenous Australian tribe of southern Queensland.
The autonym Undanbi is formed from their word for 'man' (dan).
The Undanbi spoke a dialect mutually intelligible with that of the Jagera and Turrbal peoples, and it was apparently the dialect mastered by Tom Petrie.
The Undanbi occupied an estimated 900 square miles (2,300 km2) around the coastal strip along Coolum Beach and Moreton Bay, reaching down from Noosa Heads as far south as the estuary of the Brisbane River. It extended inland, around 10 miles (16 km), to the area of Pine River, and the Glasshouse Mountains. They also had a foothold on Bribie Island.
The western neighbours of the coastal Undanbi were the Dalla.
The Undanbi were divided into hordes
Physically, the Undanbi were known for their impressive builds, which marked them off from members of tribes like the Dalla, who were generally slighter.
The Ningyningy, the most southerly Undanbi clan, are sometimes given as located also on Bribie Island. The explorer Ludwig Leichhardt, for one, in referring to the Bribie Island aborigines, wrote of them as 'Nynga-Nynga blacks.' Their dialect was called Oondoo, and their ethnonym meant 'oysters' in the Maroochy dialect. They were distinguished from the Djindubari, who used charcoal and bees' wax to blacken themselves, by painting themselves with red ochre clan markings. By the mid 1840s, it is thought that many of the encampments in the Brisbane area arose from the Undanbi remnants of the Ningyningy and Djindubari who mustered there for blanket handouts and became notorious for their pitched battles, with the Turrbal clansmen under Daki Yakka, (known to the whites as the Duke of York). By the 1850s these northern refugees were thought to be trying to exterminate the Brisbane blacks, and bought the brunt of accusations that the black presence in the area was causing endless trouble.
In colonial tradition they were reputed to be highly aggressive, though they had formerly kept the three castaways Thomas Pamphlett, John Finnegan and Richard Parsons from dying of starvation after they came across them at Clontarf Point, and by treating them hospitably for three months until John Oxley located them.
Their memory is evoked in the present-day place name for the town of Nimbi
The Brisbane horde of the Undanbi was said to have become extinct within a few decades of white settlement. Archibald Meston stated they had died off by 1860. Other testimony suggests a number were still alive, in 1883, at Mooloolaba.
Source: Tindale 1974, p. 186