Q.The 'Estimated Extent of Mongol Destruction' source box lists death-toll figures from medieval chronicles for the Mongol conquests. How did medieval chroniclers arrive at such figures?

Medieval chroniclers rarely counted the dead. Their figures were estimates, often built from a mix of battlefield reports, hearsay, and a strong dose of rhetorical exaggeration. A chronicler writing years after an event had no census, no official records, and no way to verify a number—so he worked from what he heard, what he feared, and what he wanted his readers to believe.

The numbers served a purpose beyond accuracy. A huge death toll made the Mongols seem terrifyingly unstoppable, which justified calls for unity, prayer, or resistance. It also made the chronicler's own patron or kingdom look more heroic for surviving such a catastrophe. So the figures are less a statistical record and more a measure of how overwhelming the Mongol threat felt to the people who wrote about it. …

When you open a medieval chronicle and read that the Mongols killed “a million” in one city, your first instinct is to ask: how could anyone have counted? The honest answer is that they could not, and they did not try. The numbers you see in those sources are not the product of census rolls or battlefield tallies. They are the product of a very different kind of thinking — one where a number’s emotional weight mattered far more than its arithmetic accuracy.

The chroniclers themselves were almost never eyewitnesses. Most wrote years, sometimes decades, after the events, working from the accounts of refugees, merchants, soldiers, and other travellers who had fled the destruction. These informants did not arrive with neat statistics. They arrived with terror — with stories of burning cities, piled skulls, and rivers said to run red. The chronicler’s job, as he saw it, was not to audit those stories but to preserve their horror. So he took a figure like “many thousands” and, in the retelling, it hardened into “a hundred thousand.” Each step away from the event inflated the number, not from malice but from the natural drift of oral tradition.

There was also a strong literary convention at work. Medieval chroniclers, especially in the Latin West and in the Islamic world, inherited a tradition of rhetorical exaggeration from classical and biblical writing. Numbers like forty, seventy, and a hundred thousand carried symbolic weight. A figure of “one million” was not a measurement; it was a way of saying “beyond counting.” When a chronicler wrote that the Mongols killed “three hundred thousand” in Baghdad, he was not claiming to have verified a body count. He was signalling that the slaughter was so vast it defied ordinary description. The number was a gesture, not a fact.

Religion shaped these figures too. Many chroniclers saw the Mongols as a scourge sent by God to punish a sinful world. In that framework, the scale of destruction was not just a historical detail — it was proof of divine wrath. A modest death toll would have undercut the sermon. So the numbers grew to match the moral lesson. The chronicler was not lying; he was preaching, and in preaching, the magnitude of the punishment had to be commensurate with the magnitude of the sin. This is why the most extreme figures often appear in the most overtly religious accounts. …