From farm to gun and no way back: Habsburg gunpowder production in the eighteenth century and its impact on agriculture and soil fertility

Understanding the dynamics of society’s physical exchange processes with the environment (society’s metabolism) is a major theme of long-term socioecological research. In this paper, we adapt the concept of socioecological metabolism to analyze the competition between gunpowder production and agriculture for nitrogen (N) in the pre-industrial agro-ecosystem of Pamhagen in the late eighteenth century. Saltpeter (KNO₃)—the main ingredient of gunpowder—was chemically refined from agricultural waste products, in particular manure and wood ash, which were vital for the maintenance of soil fertility. In this paper, we reconstruct nitrogen flows in the agro-ecosystem of Pamhagen and establish a nutrient balance, which allows assessing the impact of saltpeter production on agricultural soil fertility management. We find that nitrate extracted by saltpeter production in our case study was equivalent to 23 % of the total available nitrogen in manure in 1778 and 12 % in 1780. The growing demand for gunpowder and thus the artisanal production of saltpeter became influential drivers in the management of societal nitrogen flows on the local level, competing over key resources for sustaining soil fertility and leaving a substantial imprint on the nutrient budget of agricultural soils as less nitrogen was available for plant uptake.