Circa a.d. 626 volcanic eruption, climatic cooling, and the collapse of the Eastern Turkic Empire

Abstract

During the late sixth century and early seventh century, the Eastern Turkic Empire (i.e., the Eastern Turkic Khanate) was the most powerful country in the Northeast Asia. It collapsed suddenly in A.D. 630, and historians concluded that the combination of social, political and economic factors, as well as the invasion of the Tang Empire, would be the root cause. Here we suggest that a climatic cooling event ca. A.D. 627-629 could be the direct cause. In A.D. 627-629, the Eastern Turkic Empire experienced severe disasters of snow and frost. Many of the sheep and horses died. People suffered great famine and massive deaths. The Empire fell into severe national crisis and collapsed in A.D. 630. Simultaneously, the Tang Empire also experienced three successive years of frost disasters. Climatic cooling possibly also occurred in other regions. Our investigation of the ca. A.D. 627-629 climatic cooling event also improved our understanding of another problem: was the climatic event due to the impact of a ca. A.D. 626 volcanic eruption?