How Rain Helped the Mongols Conquer Asia


In the early 1200s, Genghis Khan united the warring Mongolian tribes into a mobile, efficient military state. Lashing outward in all directions from their home on Central Asia's steppe, the Mongolian armies conquered a large swath of Central Asia in just a few decades. The empire continued to expand under Genghis Khan's descendants and, at its height, was one of the largest in human history, extending from Asia's Pacific coast to Central Europe.

The Great Khan is remembered as a politically savvy leader and a brilliant military tactician, but the rise of his empire, new research suggests, might have also had something to do with a stretch of unusually nice weather.

In 2010, American researchers Neil Pederson and Amy Hessl were in Mongolia's Khangai Mountains, studying the impact of climate change on the country's wildfires. As they drove past an old flow of now-solid lava left by a volcanic eruption thousands of years ago, they saw stands of stunted pine trees growing out of cracks in the lava.

Now, as any budding naturalist can tell you, the annual growth rings of many trees reflect the conditions they grew in. A long, wet growing season results in a wide ring, and a drought-stricken year means a thin ring. After you figure out the age of a tree, these growth patterns can provide a year-by-year record of what the local climate was like. Luckily for Pederson and Hessl, these patterns were written very clearly into the trunks of their Siberian pines, which were well-preserved by the cold, dry conditions of the steppe. The pair had potentially found a wooden record of climate conditions going back thousands of years.

Pederson and Hessl took samples from 17 of the trees and found that they were indeed very old. The innermost rings of some them dated all the way back to the 7th century. Since this discovery, they've gone back and sampled more than a hundred trees in the mountains and the Orkhon Valley region, where Genghis Khan established the seat of his growing empire.

Combining their tree-growth patterns with temperature reconstructions, Pederson, Hessl, and their team pieced together a picture of what the climate was like during the centuries that the Mongols conquered and ruled.

Just before Genghis Khan rose to power, Mongolia's climate was harsh, both physically and politically. The Mongolian tribes warred against each other, and the steppe was cold and stricken by drought. Amid the conflict, the researchers say, the worsening dry conditions of the land could have been an important factor in the collapse of the old order, and paved the way for centralized leadership under Genghis Khan. "What might have been a relatively minor crisis instead developed into decades of warfare and eventually produced a major transformation of Mongol politics," they write.

Then, in the early 13th century, as Genghis Khan unified the tribes, the droughts gave way to a period when the steppes were wetter and warmer than they'd ever been. "This period, characterized by 15 consecutive years of above average moisture in central Mongolia and coinciding with the rise of Genghis Khan, is unprecedented over the last 1,112 years," the researchers say. In addition to being wet, Mongolia at the time was warm, but not exceptionally hot.

In these conditions the Mongolian grasslands would have flourished, providing fuel for the Mongolian war machine. Each of Genghis Khan's mounted warriors used several horses, and the conquering armies brought herds of livestock with them for food and other resources. The dramatic shift in temperature and precipitation came at the perfect time to provide resources for rapid military mobilization and the Mongols' early expansion.

After the empire's initial spasms of growth, the tree ring and temperature data show a return to a cold, dry climate. By then, though, the Mongols had defeated several other Central Asian powers and could exploit the conquered regions instead of relying on the grass of the steppes and their local resources.

The climate shift certainly isn't the only driver of the empire's quick rise; it might have also just been coincidental, the researchers say. To flesh out the picture that the tree rings provide, the team is working on several other studies that could corroborate their ideas. Ecologist Hanqin Tian is developing models to connect the dots between the tree-ring records of weather and grass production. Biologist Avery Cook Shinneman will analyze the layers of fungal spores from animal dung that are trapped in sediment in Mongolian lakes, which could indicate the abundance of the Mongols' livestock. Meanwhile, historian Nicola Di Cosmo will comb through records from Asia and Europe looking for historical references to the climate and the strength of the Mongolian armies.

While the tree rings provide clues about the past climate and its possible influence on the rise of an empire, they also hint that another major shake-up is yet to come in Central Asia. As they did hundreds of years ago, conditions in the region have turned from wet to arid, with long, cold winters and drought-stricken summers comparable to those experienced just before Genghis Khan seized power. During the 2000s, livestock booms went bust; millions of animals died, and hundreds of thousands of displaced herders flocked to the city of Ulaanbaatar.

Those earlier droughts happened in a much cooler climate, though. Central Asia is currently warming more than the global average, and the combination of rising temperatures and droughts, the researchers warn, could mean another era of climate-spurred social and political upheaval.

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A Very Brief History of Chamber Pots

Some of the oldest chamber pots found by archeologists have been discovered in ancient Greece, but portable toilets have come a long way since then. Whether referred to as "the Jordan" (possibly a reference to the river), "Oliver's Skull" (maybe a nod to Oliver Cromwell's perambulating cranium), or "the Looking Glass" (because doctors would examine urine for diagnosis), they were an essential fact of life in houses and on the road for centuries. In this video from the Wellcome Collection, Visitor Experience Assistant Rob Bidder discusses two 19th century chamber pots in the museum while offering a brief survey of the use of chamber pots in Britain (including why they were particularly useful in wartime).

Photo illustration by Lucy Quintanilla, Mental Floss. Saint Nicholas: HULTON ARCHIVE, GETTY IMAGES. Skulls, backgrounds: iStock
Tomb Raider: The Story of Saint Nicholas's Stolen Bones
Photo illustration by Lucy Quintanilla, Mental Floss. Saint Nicholas: HULTON ARCHIVE, GETTY IMAGES. Skulls, backgrounds: iStock
Photo illustration by Lucy Quintanilla, Mental Floss. Saint Nicholas: HULTON ARCHIVE, GETTY IMAGES. Skulls, backgrounds: iStock

Throughout history, corpses have been bought and sold, studied, collected, stolen, and dissected. In Rest in Pieces: The Curious Fates of Famous Corpses, Mental Floss editor Bess Lovejoy looked into the afterlife of numerous famous corpses, including Saint Nicholas, one of the many canonized bodies whose parts were highly prized by churches, thieves, and the faithful.

Don't tell the kids, but Santa Claus has been dead for more than sixteen hundred years. No, his body is not at the North Pole, and he's not buried with Mrs. Claus. In fact, his remains are thousands of miles away, on Italy's sunny Adriatic coast. And while Santa might be enjoying his Mediterranean vacation, he's probably not too happy about what happened to his remains. They were stolen in the eleventh century, and people have been fighting over them ever since.

Of course, the Santa Claus of folklore doesn't have a skeleton. But his inspiration, Saint Nicholas, does. That's about all we can say for sure about Nicholas: he was a bishop who lived and died in what is now Turkey in the first half of the fourth century. Legend tells us that he was born into a rich family and delighted in giving gifts. Once, he threw three bags of gold into the window of a poor family's house, saving the three daughters who lived there from a life of prostitution. Another time, he raised three children from the dead after a butcher carved them up and stored them in a vat of brine. He also protected sailors, who were said to cry out his name in rough seas, then watch the waves mysteriously smooth.

The sailors spread Nicholas's cult around the world. Within a century of his death, the bishop was worshipped as a saint, lending his name to hundreds of ports, islands, and inlets, and thousands of baby boys. He became one of the best-loved saints in all of Christendom, adopted by both the Eastern and Western traditions. Christmas probably owes something to his December 6 feast day, while Santa Claus’s red outfit may come from his red bishop’s robes. "Santa Claus" is derived from "Sinterklaas," which was how Dutch immigrants to New Amsterdam pronounced his name.

As one of the most popular saints in the Christian world, Nicholas had a particularly powerful corpse. The bodies of saints and martyrs had been important to Christianity since its beginning: the earliest churches were built on the tombs of saints. It was thought that the bodily bits of saints functioned like spiritual walkie-talkies: you could communicate with higher powers through them, and they, in turn, could manifest holy forces on Earth. They could heal you, protect you, and even perform miracles.

Sometimes, the miracles concerned the saints' own bodies. Their corpses would refuse to decay, exude an inexplicable ooze, or start to drip blood that mysteriously solidified and then reliquefied. So it was with Nicholas: at some point after his death, his bones began to secrete a liquid called manna or myrrh, which was said to smell like roses and possess potent healing powers.

The appearance of the manna was taken as a sign that Nicholas’s corpse was especially holy, and pilgrims began flocking by the thousands to his tomb in the port city of Myra (now called Demre). By the eleventh century, other cities started getting jealous. At the time, cities and churches often competed for relics, which brought power and prestige to their hometowns the way a successful sports team might today. Originally, the relics trade had been nourished by the catacombs in Rome, but when demand outstripped supply, merchants—and even monks—weren't above sneaking down into the crypts of churches to steal some holy bones. Such thefts weren't seen as a sin; the sanctity of the remains trumped any ethical concerns. The relics were also thought to have their own personalities—if they didn't want to be stolen, they wouldn't allow it. Like King Arthur's sword in the stone, they could only be removed by the right person.

That was how Myra lost Saint Nicholas. The culprits were a group of merchants and sailors from the town of Bari, located on the heel of Italy's boot. Like other relic thefts, this one came at a time of crisis for the town where the thieves lived, which in this case had recently been invaded by a horde of rapacious Normans. The conquerors wanted to compete with the Venetians, their trading rivals to the north, who were known for stealing the bones of Saint Mark (disguised in a basket of pork) from Alexandria in 827. And when the Normans heard that Myra had recently fallen to the Turks, leaving Nicholas’s tomb vulnerable, they decided to try stealing a saint for themselves.

According to an account written shortly after the theft by a Barian clerk, three ships sailed from Bari into Myra's harbor in the spring of 1087. Forty-seven well armed Barians disembarked and strode into the church of Saint Nicholas, where they asked to see the saint’s tomb. The monks, who weren't idiots, got suspicious and asked why they wanted to know. The Barians then dropped any pretense of politeness, tied the monks up, and smashed their way into Nicholas's sarcophagus. They found his skeleton submerged in its manna and smelled a heavenly perfume wafting up from the bones, which "licked at the venerable priests as if in insatiable embrace."

And so Nicholas of Myra became Nicholas of Bari. The relics made the town, and the men who stole them. The thieves became famous in the area, and for centuries their descendants received a percentage of the offerings given on the saint’s feast day. The townspeople built a new basilica to hold the remains, which drew thousands of pilgrims throughout the Middle Ages. Even today, Bari remains a major pilgrimage site in southern Italy, visited by both Roman Catholics and Orthodox Christians. Every May an elaborate festival, the Feast of the Translation, celebrates the arrival of Nicholas’s relics. As one of the highlights, the rector of the basilica bends over Nicholas’s sarcophagus and draws off some of the manna in a crystal vial. The fluid is mixed with holy water and poured into decorated bottles sold in Bari's shops; it is thought to be a curative drink.

But Bari is not the only place that boasts of the bones of Saint Nicholas. If you ask the Venetians, they will say their own sailors visited Myra during the First Crusade and stole Nicholas’s remains, which have been in Venice ever since. For centuries, both Bari and Venice have claimed the saint's skeleton.

In the twentieth century, scientists waded into the dispute. During renovations to the basilica of Bari in 1953, church officials allowed University of Bari anatomy professor Luigi Martino to examine the remains— the first time the tomb had been opened in more than eight hundred years. Martino found the bones wet, fragile, and fragmented, with many of them missing. He concluded that they had belonged to a man who died in his seventies, although because Martino was given only a short time with the bones, he could say little more.

Four decades later, Martino and other scientists also studied the Venetian bones. They concluded that those relics and the ones in Bari had come from the same skeleton, and theorized that the Venetian sailors had stolen what was left in Myra after the Barians had done all their smashing.

As for Demre, all they have is an empty tomb. And they want their bones back. In 2009, the Turkish government said it was considering a formal request to Rome for the return of Nicholas's remains. Though the bones have little religious significance in a nation that’s 99 percent Muslim, there’s still a sense in Turkey that the centuries-old theft was a cultural violation. Its restitution would certainly be an economic benefit: according to local officials, tourists in Demre frequently complain about the barren tomb, and they weren't satisfied by the giant plastic sculpture of Santa Claus that once stood outside Nicholas’s church. Even though Santa has become an international cultural icon, his myth is still rooted in a set of bones far from home.

From REST IN PIECES: The Curious Fates of Famous Corpses by Bess Lovejoy. Copyright © 2013 by Bess Lovejoy. Reprinted by permission of Simon & Schuster, Inc.


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