Only recently has it become reasonable that historians should include climate in their analyses of the past. In this case, research on grain prices during the Ming dynasty revealed that China was in lock-step with Europe in experiencing what climate historians call the Little Ice Age, extending from the start of the fourteenth century and carrying on, up and down, into the nineteenth. In this Tiger Talk, Tim Brook explains that given our growing understanding of the role of climate in human society, we have to include climate change as a determining variable in the rise and fall of states and societies.  While his recent book The Price of Collapse: Finding the Little Ice Age in Ming China is lauded as providing an entirely new approach to the economic and social history of China, Tim considers The Price of Collapse as “not a book I set out to write, but when I found the evidence, I had no choice but to write it.”