While it would seem patently obvious that geography and climate provide an indispensable framework for understanding the drama of history, historians have been wary of invoking anything remotely smacking of environmental determinism. This is in no small part because 80 years ago a Yale geographer "went too far" and argued that geography and climate were the primary factors determining history. Ellsworth Huntington created a hierarchy of civilizations based upon climactic advantage or disadvantage: cool climates stimulate civilizational energies, while tropical climates enervate. Huntington's Civilization and Climate (1924) argued that a favorably "bracing" climate enabled northern Europeans (and by extension their North American transplants) to develop the most advanced civilization in history. According to Harvard economic historian David Landes, Huntington "gave geography a bad name." The idea that geography, and especially climate, influenced history became contaminated with a determinism that to most American scholars had the odor of racism.

It would be an exaggeration to say that historians entirely neglected climate in the decades after Huntington. The French Annales school took very seriously "the history of man in relation to his surroundings." Fernand Braudel's celebrated notion of longue durÉe and Emmanuel Le Roy Ladurie's Times of Feast, Times of Famine: A History of Climate Since the Year 1000 (1971) are the most prominent Annales examples in this regard. In 1980, the Journal of Interdisciplinary History devoted an entire issue to a symposium on climate and history, but the call to consider climate afresh went largely unnoticed in historical circles. Prominent among the contributors to that symposium was American historian David Hackett Fischer, who noted that Huntington's determinism was never really refuted; it was merely ridiculed for failing "to fit the metaphysical framework of social science in the mid-twentieth century." Indeed, one of the uglier scenes I have ever witnessed at a professional historical meeting occurred in the mid-1990s when a senior world historian attempted to resurrect a version of the environmental argument, only to be treated rudely by younger historians who found his rhetoric too Huntingtonesque to be palatable. Ridicule, Fischer reminds us, is not a valid form of refutation.

No matter how they may have been misused, geography and climate are far too important to banish altogether from mainstream historical understanding. In recent years, the growing interest in world history and revival of macrohistorical analysis has helped to rehabilitate climate and other environmental factors in scholarly work, as witnessed by such important books as Jared Diamond's Guns, Germs, and Steel (1997), Landes's The Wealth and Poverty of Nations (1998), John R. McNeill's Something New Under the Sun (2000), and Felipe Fernandez-Armesto's Civilizations (2001).

A welcome addition to this literature is Brian Fagan's The Little Ice Age—a short book that tackles the important question of how climate affects history. Fagan, one of the world's leading archaeological writers and an avid yachtsman, expands his earlier Flood, Famines, and Emperors: El Nino and the Fate of Civilizations (1996) to provide a series of fascinating reflections on the extraordinarily subtle but constant effects that short-term climate changes have on human societies. Drawing upon recent advances in the field of climate studies, he illustrates how such things as tree-ring and ice-core data are providing us with a vastly more detailed and precise picture of climatic events than we could ever gain simply from a close reading of traditional textual sources. For the first time, we can study climate and temperature of the past millennium in "fine-grained detail." And when we do, our understanding of the history of Europe is enhanced.

Fagan begins The Little Ice Age with the so-called "medieval warm period" of approximately a.d. 800 to 1200. This was a period of generally benign climate and bountiful harvests in northern Europe. The Arctic pack ice receded, enabling the Norse—who were not simply pillaging terrorists, but consummate seamen, fishermen, and traders—to spread into Greenland, Labrador, Newfoundland, and even down into New England. The generally stable and warm weather also encouraged the spread of farming communities to more marginal lands at higher altitudes and latitudes, particularly in the British Isles and Scandinavia. Climate didn't cause these developments; rather, it formed an important backdrop to a whole complex of contingent cultural, technological, and economic factors, often setting limits and interjecting its subtle influence on these other factors.

A case in point is Fagan's wonderful treatment of the impact of climate on water temperatures, which in turn affected cod fishing. This might seem like a minor point until one considers that the eighth-century papal edict allowing devout Catholics to eat fish on Fridays—the day of Christ's crucifixion—gave great impetus to the salted cod and herring trade. In fact, Fagan claims that cod became a commodity with an economic impact far greater than that of gold; in turn, this fishing trade helped to transform the economy of Europe. Since cod are a highly temperature-sensitive fish, the spread of cod fishing away from the European continental shelf into waters to the west needs to be viewed not only in the light of economic (expanding European markets for salted cod), cultural (the Catholic Church's stance of eating fish on Fridays, Lent, and feast days), and technological (improvements in the design of oceangoing fishing vessels) factors, but also as a function of changes in sea temperatures as a result of climatic fluctuations.

Around 1200, we can discern the beginnings of major climatic changes that would gradually spell the end of the medieval warm period. Pack ice moved south, virtually cutting off contact between Iceland and Greenland. By 1400, the weather in Northern Europe became both more unpredictable and stormier. The so-called Little Ice Age had descended on Europe. It would last, by some estimates, into the mid-nineteenth century. The problem, Fagan points out, was that at the outset of the Little Ice Age, Europe was utterly dependent upon subsistence farming, much of it on marginal lands. Consequently, the short-term fluctuations in climate often meant disastrous harvests, which in turn led to famines, starvation and disease, and political disorder.

Fagan is at his best when he discusses the varying cultural responses to the changeable weather conditions in Europe. The Little Ice Age gave impetus to a gradual agricultural revolution in England and the Low Counties, which witnessed the introduction of clover and root crops. Cultivation of turnips and potatoes made these regions far less dependent upon cereal crops, which were at the greatest risk to climatic change. French farming, on the other hand, remained essentially medieval, which is to say it was subsistence farming overly reliant on cereal crops. Hence several bad harvests in a row, such as occurred in the late 1780s, led to food shortages and served as a catalyst to bread riots and political instability. Did climate cause the French Revolution? No. But it certainly was a background factor.

Despite his publisher's hyperbolic subtitle, Fagan is careful not to claim too much. Climate does not make or cause history. On the other hand, Fagan challenges those who have been unwilling to claim enough. In 1971, for example, even Le Roy Ladurie wrote that "in the long term the human consequences of climate seem to be slight, perhaps negligible, and certainly difficult to detect." While precise lines of historical causation will always be elusive, Fagan argues that historians should no longer allow the label of environmental determinism to prevent them from considering "the subtle effects of climatic change."

This is a wise stance. Climate is not the universal monocausal key to understanding all of history. But it is equally foolish to ignore "one of the dynamic backdrops of the human experience." Fagan's book demonstrates admirably that we gain additional explanatory power when we correlate specific climatic shifts with various economic, social, and political changes.

Fagan concludes his extended essay with a brief treatment of the steadily rising temperatures that have been recorded since the 1860s. While there is some legitimate debate about whether this global warming is the result of human activities, natural forces (especially solar events), or both, Fagan believes the odds that global warming is anthropogenic are overwhelming. By and large, he spares the reader from the often tedious global warming sermon with its obligatory anti-consumptionist "altar call," choosing instead to emphasize human vulnerability in the face of sudden climatic change. A major lesson we need to take from the history of climate is that whenever large numbers of people live on marginal lands at a subsistence level (as is the case in so many parts of the world today), changes in climate leave a lot of people dead.

It is not just historians who ignore climate at their peril.

Donald A. Yerxa is professor of history at Eastern Nazarene College and assistant director of The Historical Society.

Copyright © 2002 by the author or Christianity Today/Books & Culture magazine.
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