Tracing the environmental footprint of a Lusatian Urnfield culture stronghold in northern Poland

During the Late Bronze Age and Early Iron Age (ca. 1100–380 BCE), the lands of central-eastern Europe were inhabited by the people of Lusatian Urnfield culture (LUc). They started functioning in the 14th century BCE and erected special types of strongholds (defensive settlements). In this article, we aimed to examine if a relatively short-term process of building a stronghold might have been recorded in the palaeoenvironmental archive of the Linje mire situated near Gzin – a case study stronghold in central-north Poland. It is a pronounced structure in the landscape, but its chronology is estimated only on ceramics. Our multi-proxy palaeoecological research, confronted with the archaeological data, revealed that LUc people were present in the Gzin area at least from ca. 1040 cal. BCE. We estimated that a minimum of 20–35 ha of oak-dominated woodland should have been felled for timber consumed only for the stronghold rampart. Indeed, erecting of the stronghold was marked by a synchronous decline in Quercus, Corylus avellana and Carpinus betulus pollen values at ca. 870 cal. BCE, and coincident with increased climate instability of the 2.8 ka event. Our study suggests that humans were a significant factor enhancing the impact of the 2.8 ka event on the woodland ecosystem, as societal reaction required increased consumption of timber. Moreover, strongholds in prehistory, no matter time and location, might have significantly influenced woodland ecosystems, leaving the footprint even in remote palaeoecological archives.