After a string of major victories, the Mongol army suddenly retreated from central Europe in 1242. An analysis of tree rings and a review of historical documents suggests that the hordes gave up on conquering Europe due to wet weather.

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After a string of major victories, the Mongol army suddenly retreated from central Europe in 1242. An analysis of tree rings and a review of historical documents suggests that the hordes gave up on conquering Europe due to wet weather.