Pollution & Deforestation in the Medieval World

There has been a gross misconception since the Enlightenment, that the 8th to the 15th centuries saw no development—there was a “Middle Age” if you will. This teleology is ill-founded. Like us, they went through technological advancements, so much so that—like us—the peoples of the Middle Ages had to deal with air and water pollution, and deforestation. In fact, many people who think about climate issues limit their thinking to the late 20th and early 21st centuries.

While the issues of today’s climate are severe and require attention, it is important to understand that today’s societies are not the first to ponder climate change; in fact, people in the High Medieval Era (1100-1400 CE) dealt with similar issues.

To run farms, trees were cut down and turned into firewood, ships, and watermills. Clean drinking water was used to remove feces from the streets, and coal, charcoal, and wood were burned in cities, forcing people to breathe in hazardous material.

It is important to take a look at the problems of the Medieval Era using primary sources, as well as secondary sources where needed, and to discuss what these stories from history can tell us about current predicaments in modern society.

The Medieval Warm Period: 800 CE to 1300 CE

In order to better understand the environmental difficulties of this period, one must look at the advancements that led to these problems. To do that, we must investigate what is called the Medieval Warm Period by historians.

This period began around 800 CE and ended around 1300 CE. During it, Europe and Northern Africa saw a drastic increase in crop output, better living standards due to the increase in temperature, and small-scale colonization by the Scandinavians and later Normans. The importance of this period need not be understated, this climactic period allowed for a drastic increase in population, and during this time, cities would grow, and new settlements would be marked on the map. Cities such as Paris, London, Edinburgh, Antioch, and many more would flourish during this period.

Some have tried comparing the Medieval Warm Period to today’s climate change. In 1995, Climatologist Hubert Lamb published Climate, History, and the Modern World, claiming that the Warm Period of today is just another Warm Period in history—he was, of course, mistaken. The differences between the Medieval Warm Period and today’s climate crisis are numerous, but the reactions were similar. During this period people felt that the world would end, despite the increase in living standards, and the people of Europe and Northern Africa harvested the Earth’s resources to the point of near collapse.

The removal of forests, or wildwood as it was called, began most notably during the Roman Empire. The Romans used wood for a variety of reasons including for buildings, siege engines, farming, and heating. While the actual number of acres cleared remains unknown, these permanent forest clearings are still seen to this day. This is an important event to consider because it means that even during the early Middle Ages, forests were already beginning to disappear.

It is likely that during the Early Medieval Period, forests were seen as an intersection between wildlife and civilization, with small towns situated between two sections of forest so that wildlife could continue to flourish. Evidence for this comes from the reign of King William I of England (r. 1066-87 CE) and his Domesday Book. In most western and northern towns in England, the book mentions great distances between them, filled with forests.

The Domesday Book was made to catalog all of England, in order to improve towns, cities, and the economy. One could hypothesize that—like today—the removal of forests would have been beneficial to the overall economy and to the expansion of towns, so it comes as no surprise that this is what led to deforestation in kingdoms like England, France, and the kingdoms inside the Holy Roman Empire.

Forest removal in England began as early as the 8th century, with most of the work being done by private landowners and the king. Evidence for this comes from books like the aforementioned Domesday Book, but also other books called the Asserts which detail the amount of money paid for acres of forests removed for farms.

By the early 14th century, it is estimated that at least 70% of forests in France, England, and eastern Germany had been removed for farm expansion, waterwheel technology, or the expansion of cities (Aberth, 2013). This not only created an imbalance in local ecosystems but also likely led to air pollution through the use of coal.

While not widely used, there is evidence that suggests coal had been used in large parts of Western Europe as early as the 13th century. The use of what was at the time called “Sea Coal” in London, was likely due to the diminishing tree count. As a result, England turned to a different energy source to provide heat.

The term Sea Coal comes from the fact that coal in England mainly came from Mainland Europe (likely France and the Kingdom of Poland). Coal at this time seems to have been the major heat source for cities in England because by 1285 the public was protesting and asking the king to stop using coal.

A letter to the king’s court reads: “Commission to Roger de Northwode, John de Cobbeham and Henry le Galeys to enquire touching certain litne-kilns (rogis calcis) constructed in the city and suburb of London and at Suthwerk, of which it is complained that whereas formerly the lime used to be burnt with wood, it is now burnt with sea-coal, whereby the air is infected and corrupted to the peril of those frequenting and dwelling in those parts.”

England has the most detailed ledgers when it comes to coal, however, it is likely that cities in mainland Europe had a similar crisis around this time. Evidence for this idea comes from coal mining settlements found throughout Central Europe, where archeologists have found old coal mines in remote areas.

What likely happened was that mining towns were settled and then deserted when the Black Death began. As Dr. John Aberth points out, the Black Death allowed for the forests to rapidly regrow, due to towns and cities locking people in and out; moreover, because the idea of “bad air” was linked to sickness, coal was later avoided entirely until the 16th through 17th centuries.

Bad air and coal were not things that caused sickness during the Middle Ages, in fact, water was among the deadliest.

In water-adjacent cities, such as Alexandria, Egypt, and Paris, France, water—like wood—was an essential resource for all parts of life. The difference between water and wood, though, was that people believed water was eternal.

In the 9th century, a North African doctor named Quisti ibn Qa wrote a book on illnesses and remedies, interestingly, there are two whole chapters focused on the contamination of the water supply. This is an important fact to consider because it means even in the Early Middle Ages, people were already afraid of dirty water (at least in Northern Africa). This teleology kept growing, with more and more authors writing about the dangers of water. However, contaminated water mostly appeared in large cities like Alexandria, Mecca, and Cairo. In the 12th century, polymath Ibn Sina (Avicenna) even began separating types of water: drinking, cleaning, and cooking.

Through this information, one could infer two things. First, water contamination may have increased throughout the centuries due to rapid population increase and poor hygiene. Second, that medical doctors at the time were able to discern the problem at hand. The reason for the contamination might also be linked to a decrease of clean water. In Egypt, for example, most water was located around Alexandria and along the Nile River. Likewise, with debt becoming more frequent in the 12th century, it is possible that landowners used clean water as a means of payment, forcing peasants to drink unclean water (Duby, 1968).

Pollution and Deforestation in the Medieval World 

It is not hard to see how similar the 21st century is to the Middle Ages. The removal of forests is something that we are all too familiar with. Of course, the stories about why it is important have changed, but the reality of watching acres of trees disappear is the same. People in the Middle Ages believed that forests protected them, that fairies existed there, and that huntable animals lived inside them—in short—forests were a necessary part of life.

Today, people argue similarly, that animals need them to survive, and that humans need them for oxygen. Air pollution tells a similar story; coal is still used, and people often die from bad air. As for water, many people around the world still do not have drinkable water.

While the Middle Ages seem so distant, the fact of the matter is people from both then and now share a remarkably similar story: a story of the fear of drastic changes to the environment.

Bibliography

Aberth, J. (2013). An Environmental History of the Middle Ages. Routledge.

Bauch, M., & Schenk, G. (Eds.). (2020). The Crisis of the Fourteenth Century. Walter de Gruyter GmbH,.

Brake, W. (1975). Air Pollution and Fuel Crises in Preindustrial London, 1250-1650. Technology and Culture, 16(3), 337–359.

Brimblecombe, P. (2012). Attitudes and Responses Towards Air Pollution in  Medieval England. Journal of the Air Pollution Control Association, 26(10), 941–945.

Britain, G. (1281). Calendar of the patent rolls preserved in the Public record office / prepared under the superintendence of the deputy keeper of the records, 1281-1292 Edward I. London H.M.S.O.

Duby, G. (1968). Rural Economy and Country Life in the Medieval West (C. Postan, Trans.). Edward Arnold.

Gari, L. (2002). Abstract Treatises on Environmental Pollution up to the End of the Thirteenth Century. Environment and History, 8(4), 475–488.

Geltner, G. (2023). Ecological Impacts and Environmental Perceptions of Mining in Europe, 1200–1550: Preliminary Notes. Australian and New Zealand Association for Medieval and Early Modern Studies, 40(1), 157–180.

Hoffman, R. (2014). AN ENVIRONMENTAL HISTORY OF MEDIEVAL EUROPE. Cambridge University Press.

Williams, A., & Martin, G. (Eds.). (2003). The Doomsday Book: A Complete Translation. Penguin.