War: What is it good for?

by Ian Morris

  For the first time in history, we have semi-reliable statistics on one kind of bloodshed, in the form of western European murder trial records. These go back to the thirteenth century, and although they are difficult to interpret, riddled with gaps, and—given the incentives for lying when the stakes were so high—full of distortions, they are almost as alarming as the stories about Genghis Khan. Across England, the Low Countries, Germany, and Italy, roughly 1 person per 100 was murdered between 1200 and 1400. England was the safest place, where only 1 person in 140 met this fate; Italy, the roughest, with nearly 1 death in 60 being a homicide. (Western Europe’s twentieth-century rate, by contrast, was 1 murder per 2,388 people.)

  Western Europe was only a small part of Eurasia’s lucky latitudes, homicide was only one form of lethal violence, and the thirteenth and fourteenth centuries were only one part of the period under review here. All of this means that extracting a single figure for the rate of violent death in Eurasian lucky latitudes between 200 and 1400 is a hazardous business. We have no way to weigh up the relative contributions of homicides, vendettas, private wars, civil strife, and interstate war, but if—for the sake of argument—we just treat each of these five forms equally, we get a total rate of 5 percent for western Europe (with England at 3.5 percent and Italy at 8.5 percent).

  This figure may or may not be close to the truth (personally, I suspect it is on the low side), and whatever is true of western Europe may or may not apply to the rest of Eurasia, but it does give us a sense of the order of magnitude of the mayhem. It is also consistent with the impression provided by qualitative evidence, that the twelve-hundred-year cycle of productive and counterproductive wars between A.D. 200 and 1400 undid many of the gains made by the ancient Roman, Mauryan, and Han Empires.

  The tone of the writings surviving from the most successful of the empires between A.D. 200 and 1400, such as Tang China, hints that they may have pushed the rate of death back into the 2–5 percent range that I suggested in Chapter 2 that the ancient empires were managing, while nomad invasions and feudal anarchy clearly drove it back up. However, unless the most extreme figures for nomad massacres are actually true, rates cannot have gone back up into the 10–20 percent range that anthropologists have found among Stone Age societies. If this reasoning is right, and the rate of violent death across Eurasia’s lucky latitudes between 200 and 1400 was higher than that in the ancient empires but lower than that in Stone Age societies, the figure must have been somewhere in the 5–10 percent range.

  What that meant for the people who lived with it is hard to extract from the medieval manuscripts. My own sense of it, I must admit, has been shaped by a very different literary genre: the detective story. Under the pen name Ellis Peters, Edith Pargeter wrote twenty novels and a book of short stories about a medieval monk turned sleuth named Brother Cad-fael (played in a fine television adaptation by Derek Jacobi). Cadfael lives a quiet life, tending the herb garden in a Benedictine monastery outside the market town of Shrewsbury in England. Even so, in the eight years (1137–45) covered by the novels, by my count Cadfael runs across thirty-three murders, ninety-four men hanged after the siege of Shrewsbury, and undisclosed numbers killed in another siege and two battles (not to mention an accidental drowning and sundry assaults, whippings, and attempted rapes).

  Pargeter’s characters are cautious. They know how easily mistakes can prove fatal. Answering back to their betters invites a beating. Walking in the woods alone risks robbery and death. When the mead flows, old friends can suddenly turn into killers. And yet, despite a rate of violent death that must run to at least 5 percent, Pargeter’s people do not live in a state of constant dread, cowering in expectation of a fatal blow. The odds, after all, are nearly twenty to one in any person’s favor, but more to the point, violence was simply part and parcel of life in this brutal world. Even their entertainment was vicious. One chronicler describes how his fellows in the little town of Prato in northern Italy would nail a live cat to a post and then, with shaved scalps and hands tied behind their backs, compete to head-butt it to death, “to the sounds of trumpets.” When the people of Mons in Belgium were short of something to do, they decided—having no criminals of their own on hand—to buy a robber from a neighboring town, tie a horse to each of his ankles and wrists, and then have him torn limb from limb. “At this,” we are told, “the people rejoiced more than if a new holy body had risen from the dead.” The only upsetting thing about the episode, said the chronicler, was that the good citizens of Mons paid too much for the man.

  In a world like this, not even Cadfael could keep the Beast in its cage.

  Caging the World

  Despite all its hazards, twelfth-century western Europe was still safer than most of the planet. But that was beginning to change, because while the steppes and the Eurasian empires were locked in their bloody cycle, caging was spreading across the rest of the globe, driving down rates of violent death.

  Plenty of parts of the world have climates and soils suitable for farming, but because the distribution of wild plants and animals that could be domesticated was so uneven, the lucky latitudes were the only part of the earth where agriculture had begun within five thousand years after the end of the Ice Age. By Cadfael’s time, however, three forces had intervened to spread farming far beyond the limits of the original lucky latitudes, and in its wake caging and productive war brought Leviathans to almost every continent.

  The first of the forces was migration. Agriculture drives up population, and ever since farming began, people had responded by spreading out, looking for more land. So long as frontiers remained open, early farmers could avoid most of the effects of caging, but once the best locations had filled up, caging began trapping them on the path toward productive war.

  We see this best in the vast expanses of the Pacific Ocean (Figure 3.9). Stone Age farmers from what is now China had already colonized the Philippines by 1500 B.C., and over the next two thousand years their descendants made epic canoe voyages, rowing far out of sight of land to discover and settle the hundreds of uninhabited but fertile islands that make up Micronesia. They planted taro (a fibrous root that originally evolved in Southeast Asia), raised large families, and fought, and when their new island homes filled up, they sent out more canoes.

  Figure 3.9. The medieval Pacific Rim: sites in East Asia and Oceania mentioned in this chapter

  In the first millennium A.D. these argonauts of the Pacific spread across Polynesia, reaching distant New Zealand by 1200. A few heroes probably paddled all the way to America’s West Coast and back again (although there is no direct evidence, there is no other obvious explanation for how American sweet potatoes got to Polynesia around this time), but the three-thousand-mile trip from Hawaii to California was too far for proper migrations. This meant that by 1200 the cage was closing in the Pacific.

  We know the story best from Hawaii (largely, I suspect, because archaeologists have never needed much encouragement to work there). Humans arrived between A.D. 800 and 1000, and population boomed between 1200 and 1400. Oral traditions collected in the nineteenth century and more recent excavations agree that fighting intensified, and in the fifteenth century great warriors consolidated entire islands into kingdoms.

  The first of these was Ma‘ilikukahi, who killed all his rivals on Oahu (probably in the 1470s) and turned into a stationary bandit. He built irrigation canals and temples and centralized power in his own hands. His people, the folktales say, prospered mightily, and within a century other Hawaiian islands were acquiring even more impressive kings. Maui’s ruler Kiha-a-Pi‘ilani (who reigned around 1590), the legends say, was not just a great ruler, a fierce warrior, a fine surfer, and extremely good-looking; he was also an agricultural reformer who cleared forests and planted huge fields of sweet potatoes, as well as a peacemaker who judged his people fairly.

  On Hawaii as in Eurasia, however, the course of productive war never did run smooth. The handsome King Kiha only got to be the ruler because he fell out w
ith his older brother (who, the story runs, had thrown a bowl of fish and octopus in Kiha’s face) and split the kingdom in civil war. Out of collapse, though, came further growth. Kiha won because ‘Umi, king of the Big Island—and another famous planter of sweet potatoes—was eager to extend his influence onto Maui and sent troops to help the usurper.

  In many ways, the Hawaiian wars of unification were strikingly like the productive wars that Eurasians had fought in the millennia leading up to A.D. 200—and strikingly unlike the cycle of productive and counterproductive wars that Eurasians were trapped in between A.D. 200 and 1400. The obvious reason for this is that there were no steppes and horses on Hawaii. As a result, for every step backward, like Maui’s civil war, Hawaiian productive war subsequently took two steps forward. By the 1610s, rulers were regularly trying to get multiple islands under their control. Waikiki Beach became the favored landing spot for invasions of Oahu; centuries before the first tourist stretched out on its perfect sands, a king of Maui, a high priest from Oahu, and several thousand soldiers all bled to death there.

  In the eighteenth century, war pushed the eight islands into just three kingdoms, capable of fielding armies up to fifteen thousand strong and, in one case, a fleet of twelve hundred canoes. “Had contact with the West been delayed for another century,” speculates Patrick Kirch, the leading archaeologist of Hawaii, “one of these polities would have won out and gained control over the entire archipelago.” This was productive war with a vengeance.

  Most farmers who left the lucky latitudes in search of new land, however, were not fortunate enough to be moving into places like the Pacific, full of uninhabited but fertile islands. More often, people were already living wherever migrants went. Sometimes local foragers ran away as farmers arrived, but if they did so, they would only find that more farmers would keep coming, clearing and plowing up more forest, until the natives ran out of places to run to. And when the cage closed, hunter-gatherers faced tough choices.

  One option was to fight, burning outlying farms in bitter, generationslong guerrilla wars. The Navajo would wage just such an on-again, off-again war in the American Southwest, beginning in 1595 against the Spaniards, continuing against the Mexican government, and only ending in 1864, when the United States applied overwhelming force, devastating Navajo lands and expelling the survivors. It was just one among thousands of separate struggles. Most are now forgotten, but all ended the same way. Foragers who kept fighting were eventually annihilated, enslaved, or herded into reservations. The only alternative to destruction was assimilation, with foragers copying what the newcomers did and turning into farmers themselves. Assimilation became the second of the great forces that spread farming, caging, productive war, and Leviathans across the planet.

  The most interesting example of assimilation may be Japan. Initially, migration was more important, with Koreans bringing rice and millet to Kyushu, Japan’s southernmost island, around 2500 B.C. Kyushu was something of a hunter-gatherer paradise, with abundant wild foods that supported thousands of foragers; perhaps because of this, farming made little headway for nearly two thousand years. Only around 600 B.C., when new migrants from Korea arrived with metal weapons, did the farming frontier surge across to the main island of Honshu.

  The Japanese islands are much bigger than the Hawaiian, and so caging took longer to work its magic. It was helped, though, by three more waves of Korean immigrants between A.D. 400 and 600. These newcomers are most famous for bringing writing and Buddhism to Japan, but their crossbows, cavalry, and iron swords were even more important. The agricultural frontier moved north across Honshu, but as it did so, assimilation pushed back. Japanese chiefs seized on the ready-made revolution in military affairs imported by Korean migrants to create their own homegrown Leviathan, the state of Yamato. By 800 it had conquered most of Kyushu and Honshu.

  Over the next eight centuries, productive war united the whole archipelago. As in Hawaii, it was a bumpy ride, but each time Leviathan fell, it came back bigger and stronger than before. Yamato broke apart in the ninth and tenth centuries, and by 1100 the countryside had been overrun with private armies of the hired swords known as samurai. Fighting only turned productive again in the 1180s, when one warlord defeated the rest, got the samurai under control, and set himself up as shogun, or military governor.

  In theory, the country was run by emperors who traced their ancestry back to gods, but shoguns—usually hard, self-made men who had risen through the army’s ranks—actually called the shots. It was a messy arrangement, but it worked surprisingly well. After conquering almost all of what we now call Japan, the shoguns oversaw investments in agriculture. Productivity and population boomed, and in 1274 and 1281, Japan even beat off Mongol invasions.

  The shoguns then learned, like so many rulers in the lucky latitudes, how easily productive war could turn counterproductive when nomads were involved. To mobilize the resources needed to stop the Mongols, the shoguns had to cut so many deals with samurai and local lords that these overmighty subjects lost all reason to fear Leviathan. Across the next three hundred years, Japan slithered into its own version of feudal anarchy. By the sixteenth century (the period that Akira Kurosawa’s famous film The Seven Samurai is set in), villages, city neighborhoods, and Buddhist temples were all hiring their own samurai. Warlords filled the countryside with castles, and violence spiked up well past anything Cadfael was used to.

  Not until the 1580s did the pendulum swing back. In the years that Kiha was subduing Maui and ‘Umi was uniting Hawaii, a Japanese warlord named Oda Nobunaga stormed his rivals’ castles and deposed the shogun. His successor, Hideyoshi, went further still, pushing through one of the most amazing disarmaments in history. Announcing that he wanted to “benefit the people not only in this life but in the life hereafter,” he bullied his subjects into handing over their weapons so he could melt them down to make nails and bolts for a Buddha statue twice as tall as the Statue of Liberty. Government troops went on “sword hunts” to make sure that everyone shared in Hideyoshi’s benefits.

  Hideyoshi was not being entirely forthright, however. After disarming the people, he ramped up productive war by invading Korea, intending to swallow it and China into a single great East Asian Empire. The casualties were enormous, and when Hideyoshi died in 1598, his plan collapsed and his generals fought a civil war. Even so, his pacification of the homeland stuck. The government even demolished most of Japan’s castles: in Bizen Province, for instance, the two hundred forts that had been built by 1500 had dwindled to one by 1615. For the next quarter millennium Japan was one of the least violent lands on earth. Even books describing weapons were banned.

  By A.D. 1500, migration and assimilation had pushed farming, caging, productive war, and Leviathans far beyond their original homeland in the lucky latitudes, but in some places a third force intervened: independent invention. Several parts of the world outside the lucky latitudes had at least a few potentially domesticable plants and animals, and foragers in these regions eventually had their own agricultural revolutions and revolutions in military affairs. Despite a time lag thousands of years long, they began moving down the same path that people in the lucky latitudes had already trodden.

  Africa is a striking case in point. Migration and assimilation certainly played big parts in bringing agriculture to the continent: Africa’s first farmers were settlers from the Hilly Flanks who carried wheat, barley, and goats to the Nile Valley around 5500 B.C. (Figure 3.10). As Egyptian farmers spread into what we now call Sudan, Nubian foragers emulated them, turning to agriculture of their own accord. Eventually, when Egyptian armies pressed southward after 2000 B.C., the Nubians discovered productive war and formed their own kingdoms. In the seventh century B.C. a Nubian king—Taharqa of Napata—even conquered Egypt.

  Figure 3.10. The not-so-dark continent: sites in Africa mentioned in this chapter

  Productive war was just as messy on this frontier as anywhere else, regularly turning counterproductive and bringing on colla
pse, only to reverse itself and create a still stronger Leviathan. By 300 B.C., Napata was in decline, and a great new city was flourishing at Meroë. By A.D. 50, Meroë too was past its glory days, and the rulers of an even greater city at Aksum were raising stone pillars a hundred feet high and sending armies across the Red Sea into what is now Yemen.

  Given time, migration and assimilation might have carried caging and productive war all the way down Africa’s east coast, but homegrown caging overtook them. By 3000 B.C., people in the Sahel, the dusty grasslands that run across Africa between the southern edge of the Sahara Desert and the northern edge of the rain forest, had domesticated sorghum, yams, and the oil palm. What happened next is controversial: some archaeologists argue that eastern and southern Africans also began inventing agriculture independently, but most think that after 1000 B.C. Bantu-speaking farmers from western and central Africa migrated east and south, taking ranching, farming, and caging with them and fighting with iron weapons as they went. (Whether the Bantu learned ironworking from the Mediterranean world or invented it for themselves is yet another source of controversy.)

  Whatever the details, though, by Cadfael’s day productive war was bringing forth Leviathans everywhere from the mouth of the Congo River to the banks of the Zambezi, setting off local revolutions in military affairs. In the thirteenth century, for instance, archaeologists have detected new styles of fighting in the Congo Basin, involving larger forces, stronger command and control, big war canoes, and new iron stabbing spears for hand-to-hand combat.