Agropastoral possibilism and the trajectorial affordances of Danish inland heaths: a study of deep‐time entrapment

History does not unfold along a single trajectory, and yet the socioecological configuration of landscapes may narrow the directions history can take. This article develops a framework for assessing the directionality of history in a (pre)historic heath landscape in Denmark. To make a living from the heaths, people concentrated the heath's limited fertility through pastoralism, swidden agriculture, and/or manuring. At different points in time, the balance of these strategies differed radically. We use this insight to evaluate the trajectorial affordances of different agropastoral regimes across the longue‐durée period c.1600 BCE‐1850 CE. Trajectorial affordances is our term for describing the historical directionalities held in potential and actuated by specific human‐landscape engagements. We use our model to interrogate the seemingly linear evolution of the nutrient‐concentrating systems from ‘simple’ herding practices of the Early Bronze Age to more ‘advanced’ manure‐based agriculture in the nineteenth century. Although the nineteenth‐century system was sophisticated, it centred on a gruelling manuring practice that unleashed destructive sand drifts. We argue this mode of agriculture arose with the gradual constriction of livelihood options associated with civilizational expansion. Our analysis grapples with the open‐ended nature of human‐landscape becoming and the dynamics of what Ian Hodder calls entrapment.