Arctic terrestrial ecosystems are generally considered to be species poor, fragile and often isolated. Nonetheless, their intricate complexity, especially that of the invertebrate component, is beginning to emerge. Attention has become focused on the Arctic both due to the importance of this rapidly changing region for the Earth and also the inherent interest of an extreme and unique environment. The three archipelagoes considered here, Svalbard, Franz Josef Land and Novaya Zemlya, delineate the Barents Sea to the west, north and east. This is a region of convergence for Palearctic and Nearctic faunas re-colonising the Arctic following the retreat of the ice after the Last Glacial Maximum (LGM). Despite the harsh Arctic environment and the short period since deglaciation, the archipelagoes of the Barents Sea are inhabited by diverse invertebrate communities. But there is an obvious imbalance in our knowledge of many taxa of each archipelago, and in our knowledge of many taxa. Research effort in Svalbard is increasing rapidly while there are still few reports, particularly in the western literature, from Franz Josef Land and Novaya Zemlya. Nevertheless, there appears to be a surprising degree of dissimilarity between the invertebrate faunas, possibly reflecting colonization history. We provide a baseline synthesis of the terrestrial and freshwater invertebrate fauna of the Barents Sea archipelagoes, highlight the taxa present, the characteristic elements of fauna and the complexity of their biogeography. In doing so, we provide a background from which to assess responses to environmental change for a region under increasing international attention from scientific, industrial and political communities as well as non-governmental organizations and the general public. •Synthesize the terrestrial invertebrate biodiversity of the Barents Sea archipelagoes.•Describe each invertebrate taxon and compare diversity between the archipelagoes.•Discuss history of colonisation, paleocommunities and environmental change.•Provide a benchmark for the terrestrial ecology of a High Arctic region.•Highlight the need for continuing integrated research especially in phylogeography.