Abstract: This paper examines the topological entanglements between the naturalistic field and natural history archives, arguing that the spatial categories of ‘field’ and ‘archive’ should be considered in terms of their indexical relations. Conceptually, it points to the prosthetic qualities of the archive, namely its capacity to simultaneously delimit and expand the field by facilitating novel ways of seeing and knowing it. The field, in turn, is a necessary source of plant and animal matter without which there is no archive. Bringing together geographical literatures on ‘field’ and ‘archive’ with literature on cultures and practices of collecting, this intervention is at once conceptual and empirical. The conceptual debate is hinged to, and inspired by, the practices of collecting, classifying, and ordering Arctic ecologies by the three Oxford University Arctic Expeditions to Spitsbergen (now Svalbard) in 1921–24. These expeditions have been hailed as significant episodes in the history of ecology. While ecology as a discipline shared an ordering impulse with the archive, early twentieth‐century ecologists were explicitly distancing themselves from practices they associated with ‘armchair science’. This paper exemplifies how field–archive dialogue remained central to the practices of ecology. Reading field collecting and subsequent specimen analysis as processes of active archiving, the paper hones in on select moments and practices which connected Spitsbergen‐as‐field and UK archival institutions, such as the British Museum of Natural History. In doing so, the paper draws out the distributed nature of archive and field alike, pointing to the non‐limited locality of both localised field operations and archival practices, as well as the co‐constitutional nature of these two sites of knowledge production.