France’s Atlantic coastline, facing accelerated erosion and relentless retreating coastline, frequently reveals new archaeological remains which are threatened by rapid destruction. Several years of excavations at Amélie Nord (Soulac-sur-mer) have uncovered many archaeological structures dated from the Neolithic to Antiquity. These structures, hidden beneath the sand and located on the foreshore, are only accessible at the highest tidal coefficients and for very short periods of time. This waterlogged, anaerobic environment has preserved numerous arthropod remains for thousands of years. The archaeoentomological study of this rich corpus of insects enables us to reconstruct paleoenvironments and human activities, and to assess their impact on local insect biodiversity. Insects are thus used as bio-indicators of the anthroposystem, making it possible to characterize settlement dynamics in coastal areas and to understand the challenges faced by societies occupying these territories. Ancient populations took advantage of the resources available in this environment between land and sea. The marshes protected by the dunes were used for salt production and oyster farming, while also providing water for livestock. Trees from the surrounding forest were widely used for construction, leading to a retreat of the forest and, consequently, more open environments in Antiquity. In this changing environment, strongly subject to oceanic influences, populations also had to adapt and cope with risks. This diachronic study puts the study of climate change into a multi-millennial perspective and contributes to the development of a memory of risk.