Stancikaite, M., Sinkunas, P., Risberg, J., Seiriene, V., Blazauskas, N., Jarockis, R., Karlsson, S. and Miller, U. 2009. Human activity and the environment during the Late Iron Age and Middle Ages at the Impiltis archaeological site, NW Lithuania. Quaternary International 203: 74-90.
The authors carried out interdisciplinary research at the Impiltis hill fort and settlement area of Northwest Lithuania (56°07'23"N, 21°14'47"E) in order "to study the climate and the human impact on the landscape, the development of the settlement and the hill fort, the types of agriculture employed there, and changes in the local economy," while simultaneously "interpreted in the obtained data [were] the environmental variations produced by global climatic shifts." This work revealed that the "period of most prominent human activity in the Impiltis," as the eight researchers describe it, "was dated back to about 1050-1250 AD," and they say that "the favorable climatic conditions of [this] 'Medieval Warm Period' may have supported human activity during its maximum phase," which inference, in their words, "correlates well with the chronology of the hill fort and settlement prosperity as represented in data collected from the site."