Context: Transdisciplinary research is important where information from multiple fields is required to develop ecologically and culturally appropriate environmental planning that protects local conservation and socio-cultural values. Objectives: Here, we describe research to inform ecosystem restoration and conservation of Chumbrumba Swamp within the Wet Tropics World Heritage Area, Australia. Many such open wetlands in the region have been degraded through agriculture and pastoral production, but there has been little research into their status, history and conservation needs. Methods: The recent to pre-European settlement history of the site was explored, along with spatial variation of vegetation communities at the site, and these data integrated with historical and ethnographical information on the site and its cultural values. Results: The botanical and palaeoecological analyses showed that Chumbrumba Swamp comprises a unique and highly sensitive ecosystem mosaic with high biodiversity. An endangered ecosystem complex, 82 vascular plant species, several disjunct or endemic taxa, and species at new northern range limits were recorded within its 20 ha area. The site comprises a stable swamp site with fringing woodland and rainforest that has persisted for around 5000 years. European settlement overlaid changes in the vegetation from disturbance (e.g. fire, clearing, grazing). However, fire also affected the swamp site during pre-European times. Conclusions: Historical and ethnographic information contextualised the biophysical data and confirmed the cultural importance of the site and the dynamic interactions between ‘people and nature’. These results have been used to inform environmental restoration and validate the importance of a transdisciplinary and precautionary approach to planning wetland restoration and conservation.