Landscape and geography shape the ways people live and the kinds of societies they build. While we cannot lay it down as a rule that a particular kind of landscape always produces a corresponding type of society, there are definite patterns that can be found in many parts of the world. One important set of such patterns revolves around the interaction between mountain societies and river valley societies.

River valleys have long been centers of population and growth. Rivers provide crucial resources including drinking water, irrigation water, and fish, which allow for a large population to grow in a small area. Rivers also provide easy transport for people and goods, encouraging travel and trade. As a result, river valleys support the development of large-scale, densely populated settlements. It is no surprise that most of the world’s earliest urbanized societies emerged in river valleys, including the Nile River in Egypt, the Tirgis and Euphrates Rivers in Mesopotamia, the Indus River in India, and the Yellow River in China.

Because of the ways that river valleys encourage dense, concentrated populations, the people who live along rivers have to develop ways of managing social conflicts that aren’t necessary in more widely scattered settlements. Early valley cultures were faced with the problem of working out competing claims to resources like irrigation water and access to navigable streams. They also confronted situations in which one person’s actions, such as discharging waste into a common waterway, could affect many other people. Different cultures found different ways of dealing with these problems. Some arrived at relatively peaceful and stable solutions while others frequently fell into conflicts over rights and resources. In the end, though, many river valley cultures ended up with complex, socially-stratified societies ruled over by centralized, bureaucratic governments.

Mountain societies, by contrast, tend to be small-scale, economically simple, and egalitarian. In the mountains, crucial resources such as fertile land and fresh water tend to be scattered in small pockets rather than concentrated in large quantities. Travel is difficult and time-consuming. These facts of geography lead to people living in very small communities, individual farmsteads, or movable camps. Self-sufficiency is at a premium when you can’t easily reach out to a larger community to help solve your problems. Mountain cultures therefore tend to remain small and highly local, and to rely more on personal relationships than organized institutions. Large-scale, organized mountain empires do exist in history, such as the Inca Empire in the Andes, but they are rare.

In some mountain cultures, the very sparseness of the population helps to maintain peace—you don’t fight your neighbors if you never see your neighbors—but the same factors that shape mountain cultures also often encourage violent conflict. When resources are limited, population growth can lead to spikes of competition, sometimes escalating into violence. Without well-developed institutions for managing interpersonal or inter-family conflict, fights over land and other vital resources can spiral out of control or drag on for generations. Many mountain societies have historically been subject to frequent violent conflicts, and those who live in them develop fighting skills as a matter of course.

These basic patterns have tended to shape how mountain cultures and river valley cultures have developed in history, but neither valleys nor mountains exist on their own. When valley societies and mountain societies interacted with one another, a whole new set of dynamics came into play.

Valley societies and mountain societies have often found themselves in conflict, but it is has historically been difficult for one to decisively overcome the other. River valley societies have the resources and surplus population to field large, well-organized armies and to provide those armies with a reliable source of supplies for long campaigns. Valley armies, however, have often struggled to assert control over mountainous regions. The fragmented nature of mountains makes it difficult to move large numbers of troops and supplies around. At the same time, mountains provide plenty of hiding places for local fighters who know the terrain well. Mountainous terrain favors the kind of small, mobile, skirmishing bands and guerrilla tactics that small, feuding, fragmented mountain cultures develop. Sometimes in history, valley empires have been able to assert control over the mountains at their edges, but it requires a concerted effort. The Assyrian Empire of Mesopotamia, for instance, kept up steady pressure against the mountain tribes to the north and east, but never had much direct control over them. The Roman Empire had secure control of the lowlands on both sides of the Alps generations before it could claim success in the mountains themselves.

On the other hand, mountain people rarely have much success at invading well-developed valley cultures. While mountain warriors tend to be good at hit-and-run raiding and harassing tactics that can effectively limit a valley culture’s reach, conquering a valley takes a more coordinated effort and larger numbers of troops than most mountain societies can muster. Without a well-established centralized government, mountain armies are more dependent on ties of family loyalty and negotiated compromises that are hard to maintain far from home under the rigors of a campaign. While there are often hostilities in the hinterlands where organized, expansive river valley powers run up against the scattered but tenacious resistance of mountain-dwellers, it is rare that one side manages to decisively defeat the other.

Decisive defeats can happen, however. Sometimes, as with the Roman conquest of the Alps, Spain, Illyria, and other mountainous parts of the greater Mediterranean, river valley cultures can gather the resources and effort for a concerted push that overwhelms the locals’ ability to resist. Other times, moments of weakness in the valley can create an opening for aggressive mountain neighbors to sweep down and take control. The Zhou Dynasty in China was founded when a people from the mountainous uplands of the west seized power from the Shang Dynasty that had ruled the lowlands of the Yellow River valley. The Persians came from the mountains of the Iranian Plateau to build an empire that took in two of the great ancient river valley civilizations, Mesopotamia and Egypt. The legends of the Mexica, whom we often refer to as Aztecs, say that they came from a mountainous home called Aztlán before migrating into the Valley of Mexico and dominating it with their warriors. There may well be some historical truth behind this myth.

Not all mountain-valley interactions are hostile, however. Sometimes mountain and valley societies can coexist peacefully and profitably. River valleys produce agricultural surplus, which is often in demand in the mountains where farming is harder and less predictable. Mountains can produce useful commodities such as metals, timber, and stone that are harder to come by in the lowlands. Mountains can also be good recruiting grounds for mercenaries to build up valley armies. The rugged mountains of Greece provided trade goods and experienced warriors to Egypt and Egypt in return furnished surplus food to Greece in a relationship that was stable and mutually beneficial.

There are no hard rules in history. The study of the past is as much the study of exceptions and unexpected results as it is of familiar patterns. Still, the patterns are there. History is full of mountain people and river valley people, and the problems and opportunities that arise when they come into contact with one another.

Thoughts for writers

As always, my advice for worldbuilding is: start with the land. The ways that societies shape themselves, cope with problems, and interact with one another are always influenced by the landscape in which they were created.

The dynamics of mountain and valley societies are also applicable to other landscapes. Wherever large numbers of people settle around a shared resource—a mystical Elven city on a nexus of magic-bearing ley lines, say, or a space station guarding a hyperspace portal—similar conflicts are likely to arise, leading to a similar range of possible solutions. Wherever people live in small, scattered communities with limited resources—whether it’s desert nomads traveling from oasis to oasis or hardscrabble asteroid miners—their cultures will likely reflect many of the same influences as mountain societies. When these disparate groups of people interact, they will show the effects of many of the same forces at work between mountain and valley peoples.

The interactions of mountain people and valley people have shaped history. They can shape imagined worlds as well.

Image: Nanga Parbat, Pakistan, photograph by Imrankhakwami via Wikimedia

History for Writers is a weekly feature which looks at how history can be a fiction writer’s most useful tool. From worldbuilding to dialogue, history helps you write. Check out the introduction to History for Writers here.