This paper reports on human burials and dietary reconstructions using a combination of mortuary, isotopic data and new 14C dates, recorded on mortuary contexts excavated at Aniwa, Futuna, and Tanna islands in 1964 during Shutlers pioneering archaeological work and more recently in the course of our South Vanuatu Archaeological Survey (SVAS) project. The earliest burials date to the first millennium AD, with subsequent changes and continuities of practice into the 19th century. Isotopic results suggest an influence of geographic and environmental characteristics of each islands on their diet. Diachronic comparisons suggest a decrease in diet breadth over time without significant change in food trophic level. These variations are discussed in relation to the complex history of island settlement, adaptation, and interaction in the region and beyond. In this paper, we analyse carbon and nitrogen isotopic data measured in individuals from Aniwa, Tanna and Futuna in relation to ecological and cultural features of the islands, and discuss their variation in relation to the islands’ complex history of settlement, adaptation, and interaction within the South Vanuatu region and beyond.