More-Than-Human Geopolitics How Fishing Shapes Cross-Border Relations in the Gulf of Saint-Malo

Geopolitical processes cross spatial scales and are shaped by human and non-human actors and dimensions. We apply assemblage theory to study the cross-border relations in the Gulf of Saint-Malo, a complex marine region where Brexit resurfaced a dispute about the territorialisation and use of marine space. Using semi-structured interviews and participant observations, we demonstrate that past and current fisheries management regimes were unable to handle the fishing industry’s dynamics – emergent from interacting human and non-human elements, including fish migration patterns, the weather, and tidal variations. Anthropocentric policies introduced by Brexit further problematised fisheries management. The mismatch between the dynamic, more-than-human fisheries assemblage and the relatively static and anthropocentric management contributed to geopolitical instability. Yet, the inattention to non-human components was reinforced by coping strategies within the local fisheries sector. We highlight that multi-scalar more-than-human assemblages co-shape geopolitical situations, adding complexity and nonlinearity to what are often considered anthropogenic geopolitical disputes.