Coincidence and Complexity: Complex Interaction of Society, Environment, and Conjuncture in the Eastern Roman World ca. 500–1100 CE

The eastern half of the Roman Empire between the end of the 5th c. and the end of the 11th c. CE (customarily referred to as the Byzantine Empire) experienced several significant fluctuations in its political and economic fortunes. Climate change, disease, hostile invasions, internal strife, and subtle longer-term shifts in social and economic structures, as well as cultural ideological identities, have all been invoked to explain this pattern, yet much remains unclear. This paper comments briefly on the palaeoclimatological, palaeoenvironmental, archaeological, and historical evidence for two periods in their broader context. It points out the limitations and challenges inhering in the different types of data; it reinforces the point that changes in climate, rather than having “negative” or “positive” impacts or directly causing societal change, indirectly facilitate or frame longer-term societal transformations. As the evidence for the two case studies indicates, even at the micro-level, it remains extremely difficult in the present state of our knowledge to draw firm conclusions about the role played by climate in stimulating societal change.