Climate, Crusades and Collapse?

Upcoming Lecture: Climate, Crusades and Collapse? The Eastern Mediterranean ca. 1000-1200 (Princeton University, April 6th)

Princeton University, April 6, 2016 - 4:30pm

Location: Dickinson 211

Speaker: Johannes Preiser-Kapeller, Austrian Academy of Sciences, Institute for Medieval Research, Division of Byzantine Research

This lecture discusses a recently proposed scenario of a climate-induced “Collapse of the Eastern Mediterranean” in the 11th century AD. It demonstrates that such a scenario cannot be maintained when confronted with proxy data from various regions. On the other hand, data on the interplay between environment and economy in the Komnenian period (1081–1185) and evidence for a change of climatic conditions in the period of the Angeloi (1185–1204) is presented, arguing that climatic parameters should be taken into consideration when comparing socio-economic dynamics in the Eastern Mediterranean with those in Western Europe. The necessity of further research on the regional as well as over-regional level for many aspects of the interaction between human society and environment in the medieval Eastern Mediterranean is highlighted.

See also the forthcoming paper:  J. Preiser-Kapeller, A Collapse of the Eastern Mediterranean? New results and theories on the interplay between climate and societies in Byzantium and the Near East, ca. 1000–1200 AD, Jahrbuch der Österreichischen Byzantinistik 65 (2015) 195-242 (

Fig.: Reconstruction of climatic conditions and general trends in agricultural production in the Byzantine Empire in the 11th cent. AD


The lecture is organised within the framework of the Climate Change and History Initiative


It follows a comparative approach to climate, environment and society in Eurasia, towards understanding the impact of climate on complex societies. This interdisciplinary project will investigate the impact of climatic changes across the last two millennia on societies in two environmentally sensitive areas:

  • The eastern Mediterranean basin (including the Balkans, Anatolia and the Near and Middle East).
  • The eastern Eurasian steppe, in particular Mongolia and the regions north of China.

The main foci of the project are (1) the differential impacts of climate and environmental change on society and state formation and (2) the impact of human society and polities on the environment.

From Austria, members of the team are Mihailo Popović and Johannes Preiser-Kapeller (both OEAW/IMAFO-ABF) (