In his big new book, Global Crisis: War, Climate Change and Catastrophe in the 17th Century, distinguished historian Geoffrey Parker addresses a very big subject: a century of worldwide crises. Connecting such diverse dots as a dearth of sunspots—observed by Galileo—the collapse of the Ming dynasty in China, famine in Scotland and the Thirty Years’ War, Parker constructs a convincing case that the 17th century’s “general crisis” was the result of massive climate change. His conclusions are grounded in 36 years of asking questions and finding empirical answers in archives, mono-graphs, diaries, and all manner of printed sources in multiple countries and languages; his bibliography runs to 51 pages in 6-point type. Most important, Parker has documented how war and other social upheavals are directly traceable to perturbations of our natural world.
‘Climate does not seem to have any inhibiting effect on starting wars. But it does seem to make it difficult to finish them’
Who conceived the idea of a global crisis in the 17th century?
Voltaire, in his Essay on Customs, published in the 1760s. He put together the fact that the Ming empire fell in the 1640s just as the Fronde revolt broke out in France, just as the sultan [Ibrahim] of the Ottoman empire was murdered, just as Charles I [of England] was executed. He didn’t speculate on reasons, but he was the first person to see it—the first global historian.
What was the nature of the climate change that century?
Cooling. There is overwhelming evidence of an episode of global cooling that begins around 1618, just as the sunspots begin to disappear, and it lasts for almost a century. Sunspots are hot spots and the absence of hot spots clearly reduces the energy emanating from the sun. The sun is weaker, and the impact of that is greater in the northern hemisphere, which is where the majority of the human population lives.
Was famine the main trigger of the many popular revolts?
Right. For example, in Scotland, 1637 was the driest year in the millennium, and 1638 was close behind. Of course, the second bad year always hits harder than the first, because you have no reserves left. The Scottish government was very unpopular, because it was failing to feed its people. There are a lot of connections between short-run famine and uprisings, rebellions and revolts.
What propels countries from natural calamities to armed violence?
In some cases it’s really the only alternative—either you invade your neighbor or you die.
How did these adverse conditions lead to international military conflicts?
I don’t think we can tie European wars to the climate, but we can tie the longevity of those wars to the climate. Climate does not seem to have any inhibiting effect on starting wars. But it does seem to make it difficult to finish them. You have more war, because the wars last longer. There were several Thirty Years’ Wars in the 17th century, and I think their length was partly caused by the difficulty of mobilizing resources, which was clearly related to climate change. Wars are common at all periods. There were just more of them [during that period], because they lasted longer.
Armies often posed a threat to civil order regardless of whose side they were on. Why was that?
Armies consume a lot of food in the course of a day. How do you feed them? You take what you can find. During the Thirty Years’ War Hans Heberle from near Ulm wrote in his diary, “We didn’t take any precautions, because we thought the [Germans] were Protestants and friends like us.” Well, yes, but they were starving Protestants. He was shocked when the soldiers took his food.
Why was fighting so commonplace around the world then?
It seems to me there’s always a lot of fighting. What’s surprising is perhaps the reverse of your question. That’s to say, why, when the climate makes it so difficult to mobilize resources, do they not pack it in? Why do they not say, “Oh, we can’t go on like this; we need to make peace and start mitigation efforts”?
What prompted you to investigate climate change in the 17th century?
Something I heard on the radio. In Britain we had the Third Programme, similar to NPR. One of the interesting people I listened to in 1977 was Jack Eddy, then a very prominent NASA solar physicist. He looked at the records from the 17th century, particularly after Galileo started using a telescope to look at the sun in 1610. He saw that initially there were lots of sunspots, and then around 1640 they disappeared and didn’t return until about 1715. I thought that was fascinating and thought, Well, that’s also a period of upheavals, the rise and the fall of states, civil war, terrible famines. Could they be connected? That’s what I’ve been trying to determine ever since. That’s why it took almost 40 years.
When did you connect the dots between climate change and global upheavals?
I thought there must be a connection, but I couldn’t figure it out. And it really wouldn’t have been possible until the scientific community started to post data in the 1980s and 1990s showing year-by-year, month-by-month and, in some cases, day-by-day fluctuations in the climate.
What caused global cooling during that century?
A combination of three factors: First was the sunspots. The second was more volcanic eruptions. And third, there were twice as many episodes of El Niño—the powerful climate system that works its way across the Pacific. Normally, the winds blow from America to Australia, so they drop the monsoon. But sometimes they go the other way, and cause enormous flooding in South America and the Caribbean, and drought in East Asia and Australia.
What were the long-term consequences of this crisis?
The first and more gruesome statistic is that it seems to have killed about a third of the human population. There clearly was a catastrophic mortality in most parts of Europe and the whole of China, which is, then as now, about a quarter of the human population. There may have been communities that escaped it, but there are also communities that just disappeared.
Second, a number of states ceased to exist—the most spectacular was Ming China. The entire dynasty, the rulers of the most populous state in the world, just disappeared, murdered by the Manchus. You saw the collapse of the Stuart monarchy in the civil wars in England, Ireland, and Scotland—there were three separate civil wars—and, of course, in the colonies in America. Spain ceased to be a great power. Russia came very, very close. Poland disappeared; it was re-created but never entirely recovered from the mid–17th century. The Ottoman empire was fatally wounded by two regicides—one in 1622 and one in 1648—and never regained its power.
The third consequence is more positive: A number of intellectuals began to think that there must be something that we can do about this. The most famous example was in England, where you had the birth of the Royal Society, dedicated to trying to find ways out of the crisis. You find the same sort of movement in other European countries, in India in the 1650s, and in Japan and China.
What finally ended the 17th century global crisis?
There were fewer people. As long as you have a population that exceeds the resources available to it, you’re going to have trouble. You’re going to have popular revolts. When the population is less, even if the climate continues to be unfavorable, you can now support your population.
What are the most important lessons we can learn from this crisis?
It’s clear to me that humans had no part in the little ice age of the 17th century. I see two debates going on today:
Does climate change occur? I think after reading my book [people will see it does].
The second question is whether humans are contributing to climate change. I have nothing to offer there. But in a way that’s irrelevant to us immediately. What we need to do is learn how to react, how to respond. There I think my book has some lessons. One of them is, Don’t fight wars. Number two is, Be prepared; by looking at the 17th century and seeing how catastrophic the consequences are of not preparing, I think the book should be a wakeup call.