Books on climate change and environmental impact are apparently in fashion at the moment, and it is thus hardly surprising to find one that deals with the issue in a Roman context. Combine this with the ever-vibrant discussion of the reasons for the crisis (or should this be “crisis”?) of the third century AD and the result could easily be a very popular book. It is, however, much to the credit of the author Haas, that instead of a populist/sensationalist approach, he chooses to present a careful evaluation of all the available evidence for the Germanic provinces and Raetia of the Roman empire. Unfortunately, Haas was badly advised to use the term Nordwesten (“northwest”) in the title, as the large amount of data from Britain is largely ignored. This is not to belittle the scope of the book, which in itself is ample, but to issue a call for a similarly detailed book on the British evidence.
This study, originally a Stuttgart Ph.D. thesis, covers a wide range of evidence, historical, archaeological and environmental, and it is to Haas’ credit that he is able equally to assess the data in all three fields.
After an initial survey of the problem and definitions that underpin this study, the third chapter of the book covers the non-Christian sources of the 1st-3rd century CE and their depictions of natural and unusual/catastrophic events. The chapter carefully assesses the role of nature in literature and, leading from there, the likelihood of objective and consistent observations concerning changes in nature, which Haas considers fairly low for the study area.
The fourth chapter, “Naturkrisen bei christlichen Autoren”, repeats this survey, but focuses on the Christian sources. As is to be expected, this chapter is particularly interested in the extent to which real environmental developments and catastrophic events are portrayed when seen through the apocalyptic and eschatological lens of the early Christian writers.
The fifth chapter (“Zu den ro+merzeitlichen Umwelten im Nordwesten des Imperium Romanum”) deals with the interpretation of the literary and epigraphical material from the Germanies and Raetia with regard to the environmental situation and reviews analogies with the better (?) understood situation in the fourth century.
None of this offers much that is new to those familiar with discussions of the topic; where Haas offers significantly more is in the next two parts of the book reviewing the environmental and archaeological data.
The sixth chapter concerns the scientific evidence for a possible change in climate in the study area, both on a micro-climate level as well as overall. The chapter reviews a multitude of different techniques and sources, including ice core drilling, erosion studies based the deposition of oaks along rivers, glacier studies and palynology, to name some of the better known techniques.
An in-depth view of the very different topographical zone along the Rhine and Danube follows. These study areas differ markedly in their topographical form, the soil quality and conditions for urban development, as well as their pre-Roman (pre-)history, and this has long since been reflected in a large area of regional landscape studies. In reviewing the evidence for such diverse areas as the Lower Rhine and around Augsburg and the hill country between Mainz and the French border (to name but a few) on their own merit, Haas is able to highlight the divergent archaeological evidence as well as the possibilities available to the Roman residents for responding to any sort or crisis. He is also able to highlight areas of population reduction with areas where the settlement manages to remain fairly stable. His careful argument and review of the evidence (though at times somewhat tedious in its repetitiveness) makes this an excellent point of reference for anybody needing background information on landscape archaeology in Roman Germany; it is also able to highlight the sometimes marked quality of evidence in these areas.
The final part of the chapter 6 looks at specific architectural remains that may signal changes of climate, such as the presence of corn driers on Roman farms, drainage works, or the reduction of bath buildings. He is very careful to point out that the evidence is ambiguous at times: for example, are abandoned bath buildings a sign of deforestation and hence scarcity of wood (which might indicate high population pressure) or reduced population levels, requiring fewer bath houses?
Chapter 7 reviews the evidence from Germania Magna, i.e. beyond the Roman frontier, which, while archaeologically a lot less satisfactory, offers extremely good proof of increased erosion along the rivers and high levels of wood-intensive industrial processes. The final chapter 8 offers a general conclusion on the topic, followed by bibliography and indexes.
As this summary demonstrates, Haas’ book covers a wide area of research from critical analyses of ancient texts, to socio-historical modelling, to palaeo-scientific research and the results of (landscape) archaeology. As a result, it is highly unlikely that there will be many who will find themselves equally at ease with all parts of the book, and the two and a half pages of glossary at the end are not really adequate for an understanding of the technical terminology of the book; the reviewer (ancient historian and archaeologist, with the equivalent of a chemistry college minor) found herself reaching more than once for an introduction into palaeo-climatology to understand the ramifications of the scientific results presented here.
However, this is not to say that this book should be denied the attention of the wider academic public. Quite the contrary. There are far too many publications with far-reaching claims about the environmental situation of the Roman empire (not just in the third century), usually based on a small amount of evidence and frequently conflicting with each other. In-depth studies, such as the UNESCO Libyan Valleys Project,1 are in the minority. And while there is now increasing evidence in Britain and the Netherlands for small regions, the study presented here is one of the few that covers an area large enough to move from local weather conditions/micro-climates to statements concerning overall climatic changes.
Given the wide-ranging area of research, there are number of interesting omissions in the reading list. For North Africa the 1985 study by Burns and Denness is cited,2 but not the more recent and more comprehensive study of the UNESCO Libyan Valleys.3 As already mentioned, there is very little concerning the British Isles for a book that claims to deal with the environmental crisis of the Northwestern provinces. The latter comment is not to belittle the achievement of the book, merely to query the wisdom of claiming more in the title than is actually delivered.
Formally, the most annoying feature are the quotations, which vary from being presented solely in German translation to sections that offer both Latin/Greek as well as German translation and others that offer only the Latin or Greek. The reasons for this inconsistency are not readily apparent, but they make the first chapters as difficult to understand for non-Classicists, as the later chapters are for non-archaeologists/scientists.
The conclusions of the book are presented as a list of bullet points on two pages, but in many ways the earlier summaries for some of the regions speak for themselves:
Haas is throughout the book (esp. p. 24) keen to stress that the evidence currently available does not allow for a logically flawless study, since we are dealing with two conflicting questions, which form in effect a logical circle: a) Did something change? b) Was a change reflected and acted upon by the population it happened to? The nature of the evidence means it is not always possible completely to avoid a logical hen and egg situation, and to Haas’ great credit he points this out early in the study.
He can identify a reduction in the population in many areas, in some areas even a more or less abandoned landscape. He is thus able to substantiate that the landscape around 300 would have looked very different than 100 years earlier, but he is not able to link this beyond doubt to verified natural catastrophes, including a climatic downturn (p. 188).
Interestingly, he is able to the point to local situations that vary markedly from this overall trend (e.g., pp. 259-63) and seem to create their own micro-climates (thus creating a parallel for the current discussion in Britain about why global warming and its impact on the Atlantic conveyor might actually mean colder winters in the UK).
To put it bluntly, throughout the book he is able to point to changes, frequently for the worse, but the nature of the evidence is such that he remains unable to give a convincing answer as to the why (a phenomenon that sounds eerily familiar to followers of the current debate on climate change).
The only area where he feels confident in identifying a climatic change in the later second century AD is in Germania Magna, where the evidence for a change in the amount and speed with which the rivers flowed suggests markedly wetter conditions in these areas, leading to an increase in trees washed down by the rivers and a contemporaneous reduction in the population (pp. 271-3).
His final conclusions are, therefore, that it is not only a climatic crisis that caused the overall crisis of the mid third century. Rather, he recognizes a series of changes, changes in population patterns, soil exhaustion, changes in the uses of the existing forests, as well as climatic changes which cannot be clearly separated from each other, but which influenced each other. A global climatic downturn, possibly compounded by the Taupo eruption in 170/180 AD, is known, but its effects are hard to pinpoint, and it may locally have been counteracted or enhanced by micro climates created by earlier Iron Age and Roman human activity, such as woodland clearances. Similar changes appear also in other provinces such as Britain and may thus reflect a larger pattern.
Somebody once said that climatology is rarely easy and never simple, a fact that this book bears out beautifully. It is certainly not a book that you would give to a beginner (unless you want to give him a topic for life). An expert needing to find balanced information on the evidence available on the German and Northern Gallic provinces at the moment will find here a careful study and much to think about.
Notes
1. D. J. Mattingly and G. Barker (1996), Farming the Desert. The UNESCO Libyan Valleys Archaeological Survey. UNESCO publishing.
2. J. R. Burns and B. Denness (1985), ‘Climate and social dynamics: The Tripolitanian example. 300 BC-AD 300,’ in D. J. Buck and D. J. Mattingly (eds.), Town and Country in Roman Tripolitania. Papers in Honour of Olwen Hackett, Society for Libyan Studies Occasional Papers II. BAR Int. Ser. 274 (Oxford 1985) pp. 201-25.
3. D. D. Gilbertson and C. O. Hunt (1996), ‘Quaternary Geomorphology and Palaeoecology,’ in Mattingly and Barker (1996), pp. 49-83, as well as D. Gilbertson (1996) ‘Explanations: Environment as Agency,’ in the same volume pp. 291-317.