A Mongol siege, the Black Death, and the end of two dynasties

Society & Culture

In April 1232, a Mongol army 15,000 strong surrounded the Jin dynasty capital of Kaifeng. The siege that ensued lasted more than a year and resulted in as many as a million deaths.

This Week in China’s History: April 8, 1232

The news from Ukraine has brought sieges, unexpectedly, back to mind. For weeks, there has been talk that Russian forces would lay siege to one of Europe’s great cities, Kyiv. Although it now looks like the Russians are withdrawing and scrapping this plan, This Week in China’s History looks back to a much earlier siege at the other end of the Eurasian landmass, with a very different result: the Mongol siege of Kaifeng.

The city that today is known as Kaifeng, in Henan province, is on few tourist itineraries today, but it has a long history that includes having served as an imperial capital on eight different occasions. Located on the Yellow River, its importance grew with the completion of the Grand Canal, placing the city at the intersection of major east/west and north/south waterways. In the 10th century, the Song dynasty made Kaifeng its capital, and within 100 years it was not only the largest city in China, but probably the entire world.

Kaifeng remained the capital of the Song until 1127, when it was captured by the Jurchens, who made the city the capital of their Jin dynasty. Though the Song would endure for another century as the Southern Song, with its capital at Hangzhou, most of what is today northern China was controlled by the Jurchens: linguistically and ethnically distinct, generally considered to be the ancestors of the Manchus (who would found the Qing dynasty 500 years later).

The Jin is often thought of as a “conquest dynasty”: non-Chinese peoples who took over China and imposed imperial control over the territory. While not entirely false, the concept has several misleading weaknesses. One is that it implies that the territory of East Asia is, by default, Chinese, and that deviations from that are exceptions. Another is that there is a toggle-switch: Chinese or non-Chinese. Both of these flaws are exposed in the years leading up to the 1232 siege of Kaifeng.

The territory that is today China was, in the 13th century, divided. The Jurchen Jin — which had itself gained power by defeating another non-Chinese people, the Khitan and their Liao empire — controlled much of what is today north China and Manchuria. The Song dynasty was in power in southern China. To the west, the Dali Kingdom controlled much of modern Yunnan province; the Tangut Xia empire ruled an area comprising parts of Qinghai, Gansu, Xinjiang, Shaanxi, and Inner Mongolia. Further west, the Tibetan Empire controlled not just today’s Tibetan Autonomous Region, but large parts of contemporary Sichuan, Qinghai, and Gansu. As the title of Morris Rossabi’s book describes, it was an era of “China among equals.”

But all of these states were soon under threat by an even larger entity, one that would become the largest empire the world has ever known. By the early 1200s, the Mongols, conquering state after state, set their sights on the Jin. In April 1232, a Mongol army 15,000 strong (comprising not only Mongols but Han Chinese as well) surrounded the Jin capital, Kaifeng.

More than 100,000 Jurchen soldiers defended the city, using some of the most advanced military technology of the era, including artillery: Jurchen trebuchets hurled bombs loaded with gunpowder and shrapnel over the city wall and into the Mongol lines. Firelances, an early form of a flamethrower that projected flames 10 feet in front of an advancing soldier, were also employed.

The Jurchens held out for more than a year before the Mongols took the city. Sieges are grim: nearly all of the city’s defenders died, and the population was wracked by disease. Contemporary observers estimated that as many as a million people died in the year-long siege. A chronicler of the time, Li Gao, described the city’s agony: “Not one or two out of ten thousand of the people of the capital did not become sick, and the sick who died followed another without end. At each of the capital’s twelve gates, [the dead] sent out each day were two thousand at most and no less than one thousand at fewest, and this was so for almost three months.”

A million deaths — 40% of the city’s population, as estimated by historian Robert Hymes — is a grisly cataclysm. But Hymes theorizes that the siege of Kaifeng may be part of a far deadlier catastrophe: the Black Death. This global pandemic killed untold millions — at least 100 million and perhaps twice that many — across the globe, many of them dying in agony, covered in pustules and bleeding from all their orifices.

Historians like Monica Green have been trying to trace the origins of this plague, rewriting the timeline and route of the disease. In a 2014 article, Hymes suggests that a key part of its transmission may have been the Mongol advances of the 1200s. Plague has been established to have been endemic on the Tibetan plateau, probably carried by fleas infesting a Himalayan marmot. Hymes notes that in their campaigns of the 1200s against the Tangut Xia state, the Mongols spent two years in today’s Gansu, at the edge of the plateau. As Hymes writes, “Long encampments using carried provisions and producing heaps of refuse will attract rodent scavengers. When armies moved on, such rodents and their fleas may have hitched rides in stores and feedbags. My hypothesis requires that Gansu, in the thirteenth century, lay within the bacillus’s homeland posited by geneticists, and that of the rodents that carry it today (questions for future research); and my proposal is that the Mongols unwittingly carried rodent plague hosts and their fleas eastwards into Jin and Song China as passengers in their stores.”

In case after case, cities besieged by the Mongols in the 13th century suffered outbreak of disease, often on a colossal scale. And in nearly all cases the disease outbreak began not during the siege, but when the siege was lifted, i.e., when Mongol soldiers came into contact with the population.

But in Kaifeng, disease was rampant throughout the siege. This seems to challenge the plague hypothesis, but further inquiry shows that it, too, fits the model: in the summer of 1232, a few months after the siege began, the siege was temporarily lifted while the Jin attempted to negotiate a peace. Not only did the parley fail, but, if the plague hypothesis is right, it led to even more suffering and death.

When the siege was finally lifted, in May 1233, the consequences were brutal. The Jin emperor had escaped, but members of the royal family who remained were executed. The city was looted.

The neighboring Song, seeking revenge for the loss of their capital, used the Mongol invasion as an opportunity. Refusing Jin requests for aid — and warnings that the Mongols would turn on them next — the Song allied with the Mongols as they laid siege to Caizhou, where the emperor was making a last stand. Caizhou fell in February 1234, and with it the Jin dynasty.

As the Jurchens had warned, the Mongols then attacked the Song. In a few decades, the Southern Song had fallen, and all of China — like most of Eurasia — became part of the Mongol empire. And, if Robert Hymes’s theory is right, it also became a vector for history’s greatest pandemic.

This Week in China’s History is a weekly column.