Are Medieval Historians Just Making Stuff Up?

The monk wrote that a dragon crossed the sky over England in 793. Modern historians still quote him.

If you have ever scrolled r/MedievalHistory and thought, “Are we just making this up from a couple of monks and a half-burned charter?” you are not alone. Medieval sources are sparse, biased, and sometimes flat-out weird. Yet historians still make confident claims about population, politics, and daily life.

Medieval history often looks like guesswork because the evidence is fragmentary. In reality, historians use a small toolkit of methods again and again to squeeze hard facts out of soft sources. By the end of this, you will know five of the main ways they do that, why they can sound so sure, and where the guesswork really begins.

Historical interpretation is not random invention. It is a disciplined way of combining written sources, archaeology, and scientific data to reach the most likely explanation.

1. Source Criticism: Reading Medieval Texts Against Themselves

What it is: Source criticism is the basic method of asking who wrote a text, when, for whom, and why, then using those answers to filter truth from propaganda or myth.

Medieval chronicles are not security-camera footage. They are opinion pieces, sermons, and political spin. Source criticism treats them like that, not like neutral reports.

Concrete example: Take the famous story of William the Conqueror’s coronation in 1066. Several chroniclers, including Orderic Vitalis and William of Poitiers, describe how Norman soldiers outside Westminster Abbey heard the English crowd shouting acclamations, panicked, thought a riot had started, and began burning nearby houses.

On the surface, the story reads like chaos and misunderstanding. Through source criticism, historians notice a few things:

First, Norman writers had a reason to dramatize the scene. A wild, fiery coronation made William’s rule look like a hard-won necessity, not a polite transfer of power.

Second, the English sources are thinner and written later, which tells us more about how the event was remembered than about what exactly happened.

Third, when you compare several accounts, the details that line up (tension in London, fear of English revolt, the use of armed force) are probably more reliable than the colorful flourishes.

So historians do not just repeat the story. They strip it down. The conclusion is not “houses definitely burned at 11:37 a.m.” but “William’s coronation took place in an atmosphere of mutual fear and violence.”

Why it mattered: Source criticism turns medieval texts from a pile of legends into a usable data set. It lets historians say, with some confidence, that Norman rule in England began under the shadow of force, not consent, which shapes how we understand later rebellions and royal policy. Without this method, we would either trust the chroniclers blindly or throw them out entirely.

2. Cross-Checking: When Texts, Coins, and Dirt Argue With Each Other

What it is: Cross-checking means comparing different types of evidence, like chronicles, charters, coins, and archaeology, to see where they agree or clash.

Medieval historians rarely trust a single source. They look for patterns across different media. If a written claim matches what turns up in the ground or on a coin, it gains weight.

Concrete example: Charlemagne’s empire in the late 8th and early 9th centuries looks tidy in the written record. Royal capitularies and annals describe reforms, coinage changes, and a strong central authority.

To test this, historians look at coins themselves. Under Charlemagne, the silver denier becomes standard across wide areas. The coins carry his name and titles. Metallurgical analysis shows a relatively consistent silver content over large regions.

Then archaeology joins the conversation. Excavations at places like Aachen and other royal centers uncover monumental building projects and standardized weights. Rural digs show shifts in settlement patterns and material culture that match the timing of Carolingian reforms.

The written sources say, “Charlemagne reformed coinage and central authority.” The coins say, “Yes, someone did unify currency and control silver.” The archaeology says, “Yes, power and resources were being concentrated in these decades.” The three lines of evidence do not match in every detail, but they point in the same direction.

Sometimes they clash instead. English chroniclers describe the 9th century Great Heathen Army as a massive, almost apocalyptic Viking force. Archaeology at Repton and other sites suggests a large army, but not millions of warriors. That tension forces historians to scale the narrative back.

Why it mattered: Cross-checking stops historians from being trapped in the worldview of a single monk or court writer. It lets them correct exaggerations, confirm broad trends, and sometimes overturn long-accepted stories. When different kinds of evidence line up, interpretations become much more than “making things up” from one dusty manuscript.

3. Prosopography: Building History From Crowded Name Lists

What it is: Prosopography is the method of studying large groups of people through their names and basic biographical details, then spotting patterns in power, kinship, and careers.

Medieval documents are full of witness lists, charter signatories, and legal records. Individually, they are boring. In bulk, they reveal who mattered, who rose, and who disappeared.

Concrete example: Look at 11th and 12th century England. Royal charters, local court rolls, and monastic cartularies list hundreds of names: bishops, sheriffs, knights, local landholders.

Historians compile these into databases. They track how often a name appears, in what capacity, and near which other names. Over time, patterns emerge. Certain families cluster around the king. Others cluster around powerful earls or bishops. Some families suddenly appear after the Norman Conquest of 1066, replacing older English names.

Through prosopography, historians can say things like: “By the early 12th century, royal government in England relied heavily on a small circle of interrelated Norman families” or “English names almost vanish from the top tier of landholders in Domesday Book.”

One famous case is the study of the Anglo-Norman aristocracy. By tracking who witnessed charters for Henry I and Henry II, historians have mapped the rise of families like the de Clares or the Beaumonts, and the fall of older magnates. This method helped show that royal power was not just about the king’s will, but about a tight-knit elite whose loyalty and rivalries shaped policy.

Why it mattered: Prosopography turns what look like dry name lists into a social X-ray of medieval power. It lets historians talk about “the aristocracy” or “royal officials” as real, traceable networks, not vague categories. That makes claims about political change far less speculative and far more grounded in who actually held office, land, and influence.

4. Quantitative Guesswork: How We Estimate Medieval Populations and Plagues

What it is: Quantitative methods use partial numbers from sources like tax records, manorial accounts, and burial data to estimate things like population size, economic output, or plague mortality.

This is the part that often feels like “making stuff up.” Historians take fragmentary numbers and scale them up. The key is that they are transparent about assumptions and error margins.

Concrete example: The Black Death in England, 1348–1350. No one conducted a modern census of deaths. Instead, historians use several kinds of numbers:

Parish records in some towns show sudden spikes in burials. Manorial court rolls show tenants dying and lands changing hands. Tax records before and after the plague show drops in the number of taxpayers.

None of these cover the whole country. So historians sample. They might take a set of manors with good records, see that around half the tenants disappear, and then cautiously apply that ratio to similar regions. They cross-check with urban burial data and later wage records, which show labor shortages.

The result is not “exactly 45.3 percent of England died.” Instead, historians argue for ranges, often suggesting that between one-third and one-half of the population died in many areas, with regional variation. They debate the numbers openly.

Another case is the Domesday Book of 1086. It lists households and resources in much of England. By applying average household sizes, historians estimate total population. Different scholars get different totals, but they explain why: different assumptions about how many unrecorded people lived in each household, or how many areas were undercounted.

Why it mattered: Quantitative methods let historians say something about scale and impact instead of shrugging. They turn the Black Death from a scary story into a measurable demographic shock that reshaped wages, land use, and social relations. The numbers are estimates, not certainties, but they are disciplined estimates, anchored in surviving records rather than pulled from thin air.

5. Scientific Tools: DNA, Isotopes, and Dendrochronology Join the Party

What it is: In the last few decades, historians have borrowed tools from the natural sciences: radiocarbon dating, dendrochronology (tree-ring dating), stable isotope analysis, and ancient DNA. These methods test and sometimes overturn traditional readings of medieval sources.

Scientific dating methods give absolute or near-absolute dates to wood, bone, and parchment. Isotopes reveal diet and mobility. DNA shows ancestry and disease.

Concrete example: The so-called “Viking” mass grave at St John’s College, Oxford, discovered in 2008. Archaeologists found dozens of young men, violently killed and dumped in a pit. Early speculation tied them to a vague reference in the Anglo-Saxon Chronicle about killings of Danes in 1002, during the St Brice’s Day massacre ordered by King Æthelred II.

Radiocarbon dating narrowed the burial to around the late 10th or early 11th century, which fit the Chronicle entry. Isotope analysis of the teeth showed that many of the men grew up in Scandinavia, not England. Their bones bore weapon injuries consistent with execution or ambush.

The Chronicle gives a brief, politically charged line about the massacre. The grave, dated and analyzed scientifically, gives the bodies. Together, they confirm that the text refers not just to a policy, but to real, large-scale killing of Scandinavian men in England.

Another example is ancient DNA work on plague victims from the 14th century. By extracting Yersinia pestis DNA from teeth in mass graves across Europe, scientists confirmed that the Black Death was indeed caused by that bacterium. Genetic comparisons show how the strain spread and mutated, which helps historians map routes of transmission and timing more accurately than chronicles alone allow.

Why it mattered: Scientific methods put hard edges on fuzzy medieval narratives. They can prove that a supposed saint’s bones are centuries too young, or that a “local” burial was actually someone raised hundreds of miles away. This does not replace traditional history, but it gives historians new anchors, making some interpretations far more secure and forcing others back into the realm of speculation.

None of this means medieval historians are omniscient. They argue constantly. They revise. They admit when the evidence is too thin to say much.

But the work is not random invention. It is a set of methods for squeezing as much truth as possible from biased texts, scattered bones, and a handful of numbers. When you see a confident claim about the Middle Ages, you are usually looking at the end of a long chain of source criticism, cross-checking, prosopography, quantitative reasoning, and scientific testing.

That is why the field keeps changing. New digs, new lab techniques, or a fresh way of reading an old charter can knock down a long-accepted story. For readers, the honest answer to “are we just making shit up?” is: no, but we are constantly rebuilding our best guess, and we can show you exactly how we got there.