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Lecture: The Middle Ages (800-1350)

The settling of the Germanic tribes represents the founding of European culture. Although Greek and Roman knowledge would impact culture somewhat during the medieval period, the era from AD 800-1300 represents an explosion of technological rather than scientific development.

I consider economic change to be the driver during the Middle Ages. Politically, Europe in the early Middle Ages was a place of local culture, local politics, and local loyalties. The single unifying factor was Christianity, making the Church in Rome the spiritual center. Missionaries from Rome spread ideas of the orthodoxy of the church. By the 9th century, new invaders again insured local rather than broader interactions. Muslim Saracens launched raids on the southern coast of Europe, Slavic tribes exerted pressure from the east, and Vikings raided the northern coasts, stealing goods from churches and terrorizing the population. These new attacks would eventually, like the Germanic invasions of the western Roman empire, become migrations instead of raids. But during the 9th and 10th centuries, raids forced a local response.

Feudalism is the word most commonly used to describe the political set-up of the time. German chieftains had become kings, and they had distributed lands among their vassals as they fought for territory. One, Charlemagne, really became an emperor, a king over many states, and launched a cultural program to revive classical knowledge. Even after his empire disintegrated under his descendants, it became obvious that kings and emperors could not make an effective armed response to a coastal raid hundreds of miles away. Thus the lords controlling the land became local rulers, and often more powerful than their overlords.

Agricultural Revolution

The lands they controlled produced more wealth during this era than before, and the population grew. Towns emerged, likely at the points of trade exchanges and fairs. People in towns made their livings from trade and manufacturing, importing their food from the countryside. Agricultural surplus from the lord's manor could be sold on the market. Many history books mention the population increase first, and talk about the pressure it caused on the land. If this is true, it provided a motivation for agricultural technologies that some call an Agricultural Revolution. While that makes sense, how did this population increase occur? It would have to be from an increase in the food supply, so it is possible that a warmer, drier climate was also helpful.

Three major innovations mark this revolution.

Mouldboard plow The first was the heavy plow. Southern Europe had sandy soil, where a lightweight, wheeled plow worked well. In northern Europe, the soil was heavier, with more clay. The development of a heavier plow, with a mouldboard to turn the heavy soil over, made deeper furrows. This meant that seed could be sown more deeply, out of reach of birds and animals. That increased yields. An iron plowshare not only added to the weight but made a deeper cut. Large plows could be pulled by oxen who, though difficult to turn, were very strong.
The second was the horse collar. Before the 9th century, horses pulled plows and wagons with a harness the strapped across its neck. This put pressure on its windpipe, making heavy loads impossible (the horse would pass out). The horse collar put the pressure on the horse's shoulders, so it could pull more weight easily. Horses were easier to maneuver than oxen, and were more versatile. Although they ate more, they were faster and could increase production on a manor by 30%. horse collar
3 field rotation

The third was three-field rotation. Previously, arable land was divided into two plots - one for spring planting and the other to lay fallow (empty). This was necessary so that the fallow field would recover - if the same crops are planted year after year, it exhausts the soil and yields go down. The innovation in the medieval period was to divide fields into three parts: 1/3 for grains, 1/3 for legumes, and 1/3 fallow. This increased the amount of land in production during the growing season from 50% to 66%. The increase in food production was enormous.

There is an English nursery rhyme that starts, "Oats, peas, beans and barley grow". This was the other aspect of the innovation - the legumes planted provided more protein for the diet, which was helpful when few people could eat much expensive meat. Peas and beans are also nitrogen-fixing crops - they contain nodes on their roots that collect and store nitrogen from the air. When plowed under after harvest, these crops do more than allow the soil to rest. They help it recover quickly.



Towns and guild production

Population increase and more food meant more customers in the towns. Medieval towns were run (and often founded) by gild merchants (merchant guilds). These were organizations of merchants who controlled prices and trade within the town. Only members of the guild could buy and sell goods in the town, and by the 11th century they comprised the town government. Large towns were often "chartered" - they received a renewable lease from the lord or king who owned the land they were on, and in return paid a fixed tax. As towns expanded and more money was made, these charters were a very good deal. They paid a pittance and had total self-government.

Goods within the town were manufactured by craftspeople, organized into crafts guilds. They controlled production and prices for their section of the town economy. There were guilds of bakers, wire-drawers, leather tanners, blacksmiths and wheelwrights. The cloth industry was the largest sector of the medieval economy. There were spinners' guilds, weavers' guilds, fullers' guilds, dyers' guilds, and finishers' guilds.

The focus of my own research was fulling. Fulling is the process that follows the weaving of the spun wool into cloth. The idea is to use chemicals to treat the cloth while it's being pounded. This felts the woolen fibers together, making a soft, waterproof cloth. In Roman times, fulling was done in large, shallow troughs with stones at the bottom. The woolen cloth was laid out in the trough, and the fullers would pee into the trough, adding water and alum or fuller's earth. This provided the mix of caustic and fixing chemicals needed. Then they would walk the cloth, treading it on the stones. (If you know anyone named Walker, or Tucker, or Fuller, at least one of their ancestors was a fuller.) Afterwards, the cloth was stretched on tenter-hooks to dry, then sheared and finished.

fulling illThe major industrial innovation of the Middle Ages related to (yes!) water power. Although there has been some recent evidence of water power for an occasional industrial process in ancient Rome, almost all ancient milling was related to grinding grain into flour. Fulling appears to be the first use of the medieval innovation, the cam. The cam protruded from the waterwheel shaft, and as the shaft turned, the cams pushed down the back of a hammer, allowing it to fall. This could automate the fulling process.

Earlier mills had used the rotary motion of the wheel to create rotary motion of millstones. The cam converted the rotary motion of the wheel to reciprocal motion.

While it was possible to build a fulling mill in town, the rivers in town tended to be slow and sluggish. Waterwheels usually had to be "undershot"; that is, pushed by the slow river from the bottom of the wheel. They weren't that powerful. The great waterwheels of Rome had been in rural areas, running down hillsides with the water shooting over the top of the wheel to provide more velocity and power. But the fullers' guild held power in the towns, not outside it.

Europe's first entrepreneurs broke the rules and made arrangements for fulling mills to be built on lords' lands in areas with falling water. The guilds responded by trying to prevent industrial espionage - they posted guards at the town gates to search anyone leaving with bundles of unfulled cloth. But eventually rural watermills would use the cam to run bellows for blacksmithing, stamps for minting coins, and other purposes. In addition to the cam, a crank could also be hooked up to a waterwheel, running sawmills and pumps.

Rural water power was the wave of the future, and threatened the power of the guilds. In lowland areas with wind but no fast-flowing water, windmills did the work.

Codices, tablets and literacy

The Middle Ages also saw the invention of the codex, but very early - really around AD 4th century. I find it interesting that the book was invented about the time of the lowest literacy rate in Europe, during the Germanic migrations and the fall of the western Roman empire.

scrollWhen we think of ancient writings, like at the Library of Alexandria or in Hellenistic marketplaces, we have to think of scrolls, usually of papyrus. Parchment, made of animal skin, was also sometimes used. Since papyrus was only grown in Egypt, any interruption in trade with Egypt could cause a shortage. Scrolls are interesting pieces of technology - they have advantages and disadvantages. Writing was on only one side (the inside) of the roll, so the letters didn't touch each other, and they were durable (any damage done was usually only to the outside). Scrolls weren't always rolled - Julius Caesar was known to fold his accordian-style for easier access and storage.

codexFolding papyrus or parchment sheets into quarters or eighths and binding them at one edge creates a codex. A popular conception is that the Christian Church deliberately adopted the codex so that Christian texts would look different from Jewish and pagan scrolled works, but I haven't been able to verify that. It is just as likely that the advantages of the codex made it popular. It was easier to store, could be closed by one person (big scrolls were hard to roll), and the folded pages created an edge on which something could be written to help define it.

wax tabletGradually the codex replaced the scroll, and as it did so items that weren't converted were lost. We see this happen now - every time information storage changes format (records and cassettes to CDs, or movies to Blu-ray), some unique items are lost. Also lost may have been the linear nature of the scroll - pages are permanently stitched together in a scroll, and it doesn't require a bookmark. You are always where you left off.

In addition to the codex, the Roman period also saw the advent of tabulae, wax tablets written on with a stylus. A few of these could be tied together into a stack, and even sealed as official documents. Unlike scrolls or codices, tablets were reusable - you could melt the whole page and erase everything. They could be designed to be lightweight (certain lightweight woods or bone were often preferred) and portable, with carrying cases. They could be used for drafting letters or other documents that would later be written in more permanent form, notebooks, sketchbooks, accounting books and diaries. Charlemagne apparently wore one around his neck in his unsuccessful efforts to learn how to read and write. (1)

These means of keeping records increased in importance throughout the Middle Ages. Early Germanic settlers were not literate, and their culture kept records verbally and visually. When land changed hands, for example, a ceremony was conducted in which the seller put a clod of earth into the buyer's hand in front of witnesses. In fact, witnesses were of extreme importance in illiterate cultures, as they carried history. So did older people, who were valued for their age and memory. And lest we think that their memory was somehow faulty, the memories of people in the 4th century, say, were far better than ours.

In cultures without writing, people have prodigious memories. Medieval singers and troubadours who couldn't write would move from town to town entertaining people with stories lasting two hours or more. Entire epics were memorized and sung or spoken. Often audiences could repeat an hour-long song they'd only heard once.

Literacy enables us to write things down and record them. But literacy also means things are lost. We have already noted Socrates' concerns about writing via Plato - Socrates felt that writing entombed ideas in stone where they were harder to question. In the medieval period, as tribes and towns and people became literate, they lost their prodigious memories. Over the centuries they learned not to remember anymore, because they could always write it down. By the 20th century, I couldn't go into a grocery store without a list if I were buying more than five things. And the hypertexted nature of the internet has made our memories even worse - the understanding that we can look it up on our phone means we need remember nothing at all.

illuminationIlluminated manuscripts were also communication technology, as well as artworks. Benedictine monks in particular supported literary activities, copying ancient and medieval texts by hand, usually into codices, beginning in the 10th century. The labor of scribes and illustrators was appreciated as work appropriate to Benedictines, who considered manual labor crucial to spirituality. Monks working in scriptoria copied works on religion, botany, herbs, and medicine. They made copies of Jerome's Latin Vulgate Bible for use in churches. Monasteries could make money by selling the books, and they were needed by the 12th century for the new universities of learning. And those with artistic talent illuminated the text with images. Brilliant pigments were made of ground stone and applied with egg whites, and gold was pounded into foil sheets or powder. The illuminations took up more and more of the page as time went on - by the 15th century, when printing was popularized, some books were almost all illuminations.

uroscopySome historians believe that herbal medicine advanced most in monasteries during the medieval period, and that medical texts were of particular importance. Greek texts on medicine were often copied, preserving that knowledge. Most monasteries had an herb garden, and some monks who were experts in herbal medicine. It was a Benedictine tenet to care for the sick. That said, some historians believe that most monks were illiterate (and scribes just servants to the monastery) and learned little of value from the text they copied. The true repository of medical knowledge during the medieval period may actually have been the "wise women" who catered to the needs of sick villagers and townspeople every day. Even after medical schools were established (several at Italian universities like Salerno), when Arabic medicine was brought into the curriculum, most people trusted these lay healers.

urine flasksThere are a number of illuminations and drawings related to the practice of medicine that have survived, and one of the things I find most interesting is the pictures showing uroscopy. Some of the first writings translated from Arabic were medical treatises on diagnosis using the pulse (Galen had identified at least 27 types of pulse). The examination of a patient's urine had been done since ancient times, and took on increased sophistication in the medieval period. The image on the left shows Constantine the African lecturing on the subject (13th century). The listeners seem to have brought flasks of urine for examination or examples - the shape of the urine flask (called a jordan) changed little for hundreds of years. The illuminations and drawings showing urine for diagnosis were created in brilliant color. Diagnosis was often dependent the on the color of the urine (books refer to "black wyne" color and "liver colored", for example) (2) as well as the color of any sediment or stones. Consistency could also be better shown with color. The techniques developed for illuminating manuscripts were useful for anything requiring visual information. Art served science (or at least medical knowledge) in the development of such works.

The Gothic Cathedral

Building the Great Cathedrals.


Cavalry, cannon and warfare technologies

It is commonly thought that the development of the stirrup, a simple device, holds huge importance in medieval warfare. Stirrups likely came into use by cavalry around the 8th century. They provide for faster mounting and dismounting, and enable greater stability on the horse, particularly when wielding weapons. Interestingly, for awhile historians equated the stirrup with the rise of feudalism as a political system. While this view has fallen into disfavor (particularly because the Byzantines and Arabs adopted the stirrup around the same time, but not feudalism) the two do coincide. Stirrups made cavalry much more effective as a fighting force.

Medieval warfare focused on capturing and holding fortified outposts and the lands they defended. In 1095, Pope Urban II called the first international Crusade to the Holy Land. In addition to increasing his own power as pope (because he could call on soldiers from all nations), Urban was trying to redirect internal European violence caused by the cessation of localized warfare with invaders. By 1095 there were no more raids, and yet everywhere knights trained and lords fought with each other, having nothing else to do with the militarized system of feudalism. Urban saw a way to turn this violence to "good" by fighting the non-Christian forces who had occupied Jerusalem for hundreds of years. Crusades thus added another element to warfare, since with a Crusade long distances had to be covered with a great deal of equipment.

Siege warfare was the primary form of war in the medieval period. Whether on Crusade or fighting a local lord, territory could only be won by capturing the stronghold. Thus many technologies were focused on battering down walls and gates, and interfering with supplies of food and water. Pitched battles on battlefields could be profitable, however, if one captured a high-ranking member of the enemy and held him for ransom - most kings that engaged in combat were at one time captured and ransomed back. Some historians believed that full engagement was avoided when possible, as it was costly and difficult to hold territory through field combat. Castles were chosen strategically to be fortified as strongholds or left to fall. Sieges, by their nature, could be lengthy, continuing into bad-weather months and leading to disease among the troops. Crecy

On the battlefield, the most interesting aspect of late medieval warfare was the shift in archers' equipment. The Battle of Crecy is famous for the defeat of the French crossbowmen at the hands (or arrows) of the English longbowmen. Archers were important because, if they could achieve accuracy at a distance, they could stop a cavalry charge. The crossbow (known as a ballista in ancient times) used a channel and bolt to achieve a range of about 380 yards. They were heavy and hard to tilt upward to get better range, and the iron rusted in the rain, but they were fairly easy to use and the bolts could pierce armor. They also didn't need much strength, since a mechanical gear pulled back the string. The English bow, later called the longbow, was impervious to weather, because it used resin instead of iron and glue to hold it together, and was often made by the man who wielded it. Since they used no metal, they were lightweight and cheap for thousands of men to carry. In England those who didn't hold much property were commanded by law to have and practice using a longbow. In the hands of a longbowmen, many more arrows could be fired per minute than with the crossbow, raining down (cheaper) arrows on the enemy.

By the 16th century, however, the longbow itself was being challenged by firearms, in particular the arquebus or "hackbutt".

But back to siege warfare, where cannon were being improved to knock down walls. Cannons were first used in the 14th century, and they were tricky devices - many of them blew up and killed the gunners. Cast iron, for example, would burst if it wasn't made properly and contained any phosphorus. Cannons didn't have much distance accuracy for the first couple of hundred years of their use, but the propelling of a spherical ball into a castle wall at point-blank range could be very effective in a siege.

The noise of both cannons and hackbutts also frightened horses, which could be useful.

Rediscovery of Greek knowledge

Of great significance to the intellectual life of the Middle Ages, and ultimately of the Renaissance, was the fall of Toledo to Christian troops in 1085. This led to the discovery of the Arabic works preserving and adding to the works of ancient Greece, and their translation by Jewish scholars.

It would be some time before anyone other than educated abbots and wealthy aristocrats would make use of the new texts. The medieval Church was concerned, also, about the value of such pre-Christian texts in the community of Christendom. Such works could be dangerous if they focused on individual achievement over the goals of the Christian community, or worldly victories without the hand of God.


My own work in college and graduate school, briefly explained above, was focused on the conflict between merchant and crafts guilds over the fulling mill. I showed that this conflict led to the merchant entrepreneurs' success in moving fulling to the countryside, where there were no guild restrictions and where falling water made the mills more efficient. At the time, a popular book was Jean Gimpel's The Medieval Machine (3), and the fulling mill was clearly one of many machines that created what Gimpel called a medieval industrial revolution. Since then, more evidence has come to light indicating the possibility of such mills in earlier times. This new research lends even more credibility to the idea of an industrial continuum, with technological knowledge continually gained and lost, rather than "revolutions" at certain times. I'll discuss this further when we get to the 19th century's "industrial revolution". At the time I was studying the Middle Ages, many people still thought it was a time of darkness and superstition, rather than intellectual and mechanical progress. As we continue to study history, we find more and more abilities, machines, ideas and achievements in past eras than we thought.


(1) Michelle P. Brown, The Role of the Wax Tablet in Medieval Literacy: A Reconsideration in Light of a Recent Find from York, 1994.
(2) Peter Murray Jones, Medieval Medicine in Illuminated Manuscripts (The British Library, 1998).
(3) Jean Gimpel, The Medieval Machine: The Industrial Revolution of the Middle Ages (London: Gollancz, 1977).