Why War?

by Richard Overy

Why has war been a consistent presence throughout the human past? A leading historian explains through rich examples and keen insight.

In 1932, two towering intellectuals, Einstein and Freud, published a correspondence on the question, “Why war?” Their exchange presented war as an instinctive drive, a conclusion seemingly confirmed in the carnage of the coming world war. But their narrow response left many other explanations What about war and the competition for resources? the need for security? the passions of belief, ideological or religious? What of leadership and the impulse to power?

Showing remarkable range, Richard Overy explores the title question throughout human history. He reconstructs long-ago conflicts among hunter-gatherers from Africa to the Americas using skeletal and climatological evidence of the Neolithic period. He draws on Roman history to weigh the empire’s voracious appetite for resources. He demonstrates the drive for power through the examples of Alexander the Great, Napoleon, and Hitler. And he shows through the current war in Ukraine how the various impulses to war overlap and reinforce.

Genres: History, Nonfiction, War, Politics, Military History, Military Fiction, Philosophy

Kindle Edition

Published June 4, 2024

About the author

Richard James Overy is a British historian who has published extensively on the history of World War II and the Third Reich.

Educated at Caius College, Cambridge and awarded a research fellowship at Churchill College, Professor Overy taught history at Cambridge from 1972 to 1979, as a fellow of Queens' College and from 1976 as a university assistant lecturer. In 1980 he moved to King's College London, where he became professor of modern history in 1994. He was appointed to a professorship at the University of Exeter in 2004.

His work on World War II has been praised as "highly effective in the ruthless dispelling of myths" (A. J. P. Taylor), "original and important" (New York Review of Books) and "at the cutting edge" (Times Literary Supplement.)[

Reviews

[Ieva · Rating 5 out of 5]

Interesantas britu vēsturnieka pārdomas par jautājumu, kas arī mani nodarbina jau ilgu laiku – “Kāpēc karš?”. (Iespējams, ka šis ir spoileris, bet vai tiešām kāds gaidīja citu atbildi) Jautājums ir labs, bet diez vai pa īstam tā konkrēti atbildams.
Bet filozofiskais ieskats antropoloģijas, psiholoģijas, bioloģijas, ekoloģijas, reliģijas un vēstures perspektīvās ir ļoti labs. Izvēlētie piemēri arī ir visplašākie, sākot ar neolītu (un pat pērtiķveidīgajiem līdz tam) fortifikācijām līdz Putina Krievijai, no Romas Impērijas līdz mūsdienu klimata-sausuma karstajām vietām un potenciālajam ekoloģijas krīzēm.
Šī nav grāmata, kas mierinās ar universālu atbildi, bet jā, kara koncepts vienkārši ir civilizācijas daļa, lai cik neprātīga un negribēta.

[Jarek Schmanski · Rating 3 out of 5]

Why war?

Answer: Eight distinct reasons that make up the eight sections of the book and that all can plausibly be attributed to cause war. Not super satisfying.

While I respect the honesty in recognizing there’s no surefire biological, psychological, or philosophical reason behind why war happens, the author dilutes whatever argument they hope to make.

Sort of interesting material, but not much of a page turner. At times, it felt more like a literature review than a coherent response to the question.

Wouldn’t recommend unless on sale. Cover’s cool, though.

[Ty · Rating 4 out of 5]

4.25⭐️

Overy asked “Why War?” And boy did he answer. On some level, I believe that war is a question that can be answered by facts and lines drawn between biological results. But here’s the thing, if war were as simple as an eight part series, wouldn’t we have come of with some solutions? And Overy acknowledges that in the last chapter.

My favorite chapter was the one on security, because it covered modern warfare the most extensively! So interesting. I would absolutely love to have a conversation with Overy himself, because this book was quite factual, it doesn’t cover his individual opinion.

I did have a very hard time believing that war is in our genes. It seems to me that a vast majority of us aren’t dedicated to the destruction of other human beings, but actually to peace. I really enjoyed this book. It got me out of a book slump. Does that mean that I agree with all the conclusions that were drawn in it, no it does not. I look forward to reading more on this subject.

Definitely recommend!

[Cgcang · Rating 2 out of 5]

Underwhelming and just a bit boring. Maybe it simply was not meant for me.

[Louis · Rating 2 out of 5]

learned lots but was not having a good time learning lots. hugeeeee variance in my interest level based on the chapter, some i did genuinely enjoy but so many were just such a slog and not communicated very well

[Chad Manske · Rating 4 out of 5]

Richard Overy’s “Why War?“ is a compact, lucid, and unsettling meditation on why organized violence has shadowed human society from its earliest traces to the nuclear age. It is less a narrative of particular campaigns than a guided tour through the main explanations scholars have offered for war—and why none of them, on their own, quite suffice. Overy divides the book into two broad halves: deterministic explanations of war and motivational ones. The first half ranges across ‘biology,’ psychology, anthropology, and ecology, asking whether humans are hard‑wired, culturally trained, or environmentally pressured into conflict. The second half shifts to human cognition, exploring war as a choice shaped by resources, belief, power, and security. The book’s central claim is that war is neither a recent aberration nor the product of a single cause; it is a recurrent pattern emerging from the interaction of innate tendencies, cultural norms, and calculated interests. Overy is especially effective at dismantling monocausal theories, from crude evolutionary determinism to purely structural accounts that treat leaders as prisoners of systems. He insists on human agency: wars happen because specific actors, in particular circumstances, decide that violence is preferable to the available alternatives. Several chapters stand out, notably the anthropological sweep that challenges the idea that war was merely “invented” in complex societies, and the resource chapter that links climatic stress, scarcity, and organized raiding across eras. The discussions of ‘power’ and security are equally sharp, pairing figures from Alexander to Hitler with modern cases to show how status, fear, and prestige feed into decisions for war. For readers in strategic studies, the treatment of security dilemmas and Hobbesian pessimism will feel familiar but is rendered with unusual historical breadth. At roughly 230 pages, the book is tightly written, heavily footnoted, and surprisingly accessible given the range of disciplines it synthesizes. Overy warns that this is not a grand theory of declining or rising violence, but a mapping of how different fields have tried to answer Einstein’s question to Freud about escaping the “menace of war.” Some reviewers fault his refusal to offer a single, bold answer, yet that restraint is arguably the book’s most intellectually honest—and intellectually ‘provocative’—feature.

[Laurent Franckx · Rating 3 out of 5]

Although Overy has dedicated his career to writing about war, this book is a bit of an outlier, as it is less about the history of an individual conflict, than about the causes of violent group conflict in general. Overy ventures far outside his comfort zone as a historian, and addresses in turn biological, environmental, psychological and anthropological explanations. His final conclusion (that there is no monocausal explanation for war) may seem disappointing to some, but I think this exactly the most important contribution of the book. A lot of "explanations" of war were driven by wishful thinking ("war is an anomaly and if we understand, we will be able to prevent it"), and Overy's final point that war may not just have a long history, but also a future, may appear cynical, but acknowledging this point is probably the first step in being better at preventing it. Si vis pacem, para bellum, as it were.

[Marty Webb · Rating 3 out of 5]

Great premise, I personally was let down in the execution.

[Rachel · Rating 3 out of 5]

In his introduction, Overy admits that he is a scholar of WWII and this is the starting point of all his work. Indeed, many of the examples are over-weighted in favour of not just Hitler’s Germany but also the natural precursors, to wit, Alexander the Great and Napoleon. Perhaps the issue is that the subject is too vast to be whittled down to a yes/no binary conclusion. Overy skips all over history, from the minimal archeological evidence of pre-history that suggest humans were violent back then, too, but would you call it war? This is an unanswerable question, given the lack of record. I think the argument that religious wars are indeed something to do with religion is probably necessary academically but stupid generally. Just because the Western audience of this book has been socially secular for a few generations doesn’t eradicate the real and present fear of God and Hell that tormented our (recent) ancestors. Overall, Overy doesn’t seem sure himself what to conclude based on the collated evidence he presents. He may have been better off writing a less-researched personal polemic, or sticking with just facts, rather than trying to use said facts in a one-sided air debate.

‘These [group] mechanisms are distinct from the psychology of individual or personal aggression, because by definition it is the capacity to cooperate that makes collective violence possible.’

I must say this was a new thought to me, and an unpleasant one.

‘Without the possibility of selling the resources, usually illegally, there would be no point in controlling them.’

‘The construction of value explains why wars are fought for resources, from slave raiding in the classical world to looting the diamonds and oil of today.’

This point, which is the conclusion rather than the opening statement of the ‘resource’ chapter, is one I feel bears more interrogation. The value of slaves as a resource is ultimately to free up non-slaves from back-breaking labour. The possession of diamonds also achieves this but in a more roundabout fashion. Ultimately, if no one wants a diamond, you can’t use it to hoe a field, but you can do so with a person.

[Don Heiman · Rating 4 out of 5]

In 2024 W.W. Norton published Richard OVery’s book “Why War?” The book begins with a very interesting prologue about the history of warfare from the Neolithic period and European Linear Ceramic cultures 7,000 years ago to the present day war conflicts between Ukraine and Russia. The book also has two major sections. The first section (Part 1) is about wars that are caused by biology, psychology, anthropology, and ecological conflicts. These discussions feature a variety of warfare “triggers” that caused many wars from prehistorical times to our current age. This research is based on an analysis of war related artifacts, written historical warfare documents, and conflicting tribal social/religious beliefs. The second section (Part 2) of the book has chapters about the resources, belief practices, community power structures, and security fears of tribal and international world leaders. I was very impressed by OVery’s research findings about the conquest activities of Julius Caesar, Alexander the Great, Napoleon, and Adolph Hitler. His research also references advanced technologies that can cause warfare. Finally, I found many of Richard OVery’s warfare hypotheses very fascinating—especially his hypotheses about Freudian “death drive” notions and Einstein’s theories about how best to handle international “menace of war” fears. For me, Richard Olvery’s book was a wonderful learning experience. (P)

[Stephen Harrison · Rating 3 out of 5]

This book asks the big question, "Why do people fight wars?" His overall argument is that human's aren't built to inevitably fight, but have created social structures that make fighting more likely and acceptable. These structures come in many forms but can largely be broken down as economic, political or idealogical. Some societies have lived without war for long periods of time, but most of the major civilizations have seen war as a consistent part of life. He also argues that war is a defining part of modern society and those who argue that liberal values will make it less frequent or disappear are overly optimistic.

I found the book largely persuasive and largely not impressive. It must have taken a bunch of research to bring in all the information he has going from prehistoric humans to the current Russia-Ukraine War, but his conclusion isn't exactly a revelation. He argues that even when you can isolate a single cause for a particular war, you still won't have an adequate explanation without looking at other contributing factors. I kind of expect him to finish with "It's complicated". Overy is a great historian and I have loved the three other books I have read by him, but this one just didn't work for me.

Summary:

Overy defines warfare as organized violent conflict and looks at a broad range of research on why people engage in that when it is inherently destructive, especially with modern weaponry. Overy breaks things into nice digestible segments that are arranged around different issues. The first half of the book looks at potential causes within humans while the second looks at potential external causes. I have a brief summary of them below.

Part I-
1. Biology - are humans biologically disposed to fighting? Overy looks at research done by biologists and anthropologists to suggest that there is a possibility that humans have evolved innate reactions that make them more likely to violence and warfare, although the evidence is not so clear as to have a consensus. It is possible that the desire to fight makes one survive better and the more willing (and stronger) fighters would live to reproduce.

2. Psychology - He starts with early psychologists' attempts to explain World War I and then World War II. He looks at the suggestions of a "death drive" made by Freud, which isn't particularly convincing. On the other hand, the idea of "us" vs "them" reaction makes a lot of sense. Othering people outside of the tribe establishing clear lines of who to trust and think of as a person, which makes it easier to inflict violence against those who aren't part of that. This has been true from at least the Peloponnesian War and is probably still true in the war in Ukraine today.

3. Anthropology- Overy looks at the historical prevalence of war across cultures, challenging the notion that early human societies were peaceful. He argues that, although we may not know the reasons for war, archaeological evidence strongly suggests warfare has been a consistent aspect of human history.

4. Ecology - This analyzes how environmental factors and resource scarcity have lead to conflict. Overy notes that while ecological pressures can contribute to war, they are often intertwined with other social and political factors. It seems common sense that changes in the environment led to conflict, but Overy argues that is not as clear cut as that.

Part II: Human Agency and the Drivers of War

5. Resources - Overy looks at how competition for resources like land, oil, and water has historically led to conflict. He argues that while resource acquisition can be a factor, it, like ecology, often intersects with political and ideological motives. He brings up some interested historical examples of where it has been assumed that the war was for resources, but the historical documents suggest otherwise. One that surprised me was the Boer War, which, according to Overy, wasn't driven by the mining companies or even the government wanted access to diamonds and gold, but was more about the UK government wanting to spread the empire and control over larger areas. I have always taught that it was about acquiring resources but will have to rethink that.

6. Belief - Explores the role of religious and ideological beliefs in motivating war. Overy examines cases like the Crusades and modern jihadist movements, arguing that belief systems can be powerful drivers of conflict, although even then there are likely other important factors that underly those beliefs.

7. Power - Overy analyzes how the pursuit of power and dominance can lead to war. Overy discusses historical figures like Alexander the Great and Hitler, specifically looking how personal ambition and state interests can result in conflict. For personal ambition, it could either be an individual's desire to be remembered as a great man or as a means to gain further control of the country he is governing. Sometimes is connects to nationalism and/or racism with societies wanting to demonstrate their strength and rightful place in the world.

8. Security - The desire for security and fear of threats can precipitate war. A lot of security studies have focused on the military aspect of this, but Overy suggests that the discipline's recent expansion to look more at economy and ecology have helped explain the security aspects more thoroughly. He also discusses the concept of preemptive strikes and the role of misperception in escalating tensions, suggesting that a lot of conflicts are not entered into rationally and with purpose, but are from mistakes and miscalculations.


Conclusion
Overy concludes that while war has been a persistent feature of human history, it is not inevitable. He emphasizes the importance of understanding the multifaceted causes of conflict to better prevent future wars.

[Ginger Griffin · Rating 4 out of 5]

Post-election note: When it comes to war, the most dangerous combination seems to be an extremely narcissistic leader + obsession with military conquest. Examples from history include Alexander the Great, Napoleon, and Hitler. Many (if not most) leaders throughout history have been narcissists to some degree. But most probably have not reached the extremes of someone like Napoleon. And most who do may be obsessed with things besides military conquest (having the biggest palace or the most fawning retinue, for example). So maybe we're lucky that Trump got a draft deferral for bone spurs and seems to have little interest in conquering other countries on the battlefield (economic conquest is another matter). Given Trump's level of narcissism, an obsession with military conquest would greatly increase the chances of World War III.

Are humans wired for war? Not exactly. Though certain evolved traits probably predispose us to it. Some supplementary notes on _Why War?_

The author offers a good catalog of war’s proximate causes (resource conflict, security, predation). But he doesn’t offer much detail on the underlying factors that incline humans to fight wars. We need some other sources for those factors, so:

*We’re primates, and primates seem particularly prone to intra-species killing, especially coalitional killing. One (somewhat controversial) study concluded that primates are six times more likely than other mammals to kill members of their own species. Gomez et al (2016) “The phylogenetic roots of human lethal violence”
https://www.nature.com/articles/natur... Yong (2016) “Humans: Unusually Murderous Mammals, Typically Murderous Primates” https://www.theatlantic.com/science/a...

*Chimpanzees, our close primate relatives, form coalitions to attack and kill con-specifics. Sometimes two or more lower-ranking males gang up to attack a higher ranked male within the troop. More often, gangs of males opportunistically attack members of another troop (presumably because they see the other troop as a resource rival), sometimes striking repeatedly until the rival group is destroyed. Mitani et al (2010) “Lethal intergroup aggression leads to territorial expansion in wild chimpanzees” https://www.sciencedirect.com/science... Our earliest hominin ancestors (who split from a common ancestor with chimpanzees around 6 million years ago) probably shared this propensity for coalitional violence against other members of their species. Wrangham (1999) “Evolution of coalitionary killing” https://pubmed.ncbi.nlm.nih.gov/10601...

*Out of necessity, early hominins probably began living in larger social groups (and behaving more cooperatively within those groups) as they moved out of the trees and into a terrestrial environment. Group cooperation may have been the only way to survive for an animal that couldn’t run as fast as a gazelle or wield its teeth and claws like a lion. Raihani (2021), _The Social Instinct_ https://www.amazon.com/Social-Instinc... ; DeSilva (2021) First Steps: How Upright Walking Made Us Human https://www.amazon.com/First-Steps-Up...

*But living in larger groups probably also meant more opportunities for conflict. How to deal with that? As hominins evolved, aggressive tendencies changed. Scientists often distinguish between two different types of aggression: proactive and reactive. Proactive aggression is intentional and planned, while reactive aggression is impulsive and anger-based, usually resulting from frustration or perceived provocation. The two types of violence appear to be mediated by separate neural mechanisms (and thus may be subject to separate evolutionary pressures). During hominin evolution, proactive violence probably remained at the chimpanzee level, while reactive violence declined sharply. Chimpanzees can exhibit hair-trigger aggression toward other members of their troop that annoy or frustrate them, which results in frequent angry skirmishes (generally nonlethal, but disruptive). Prevalence of such clashes is much higher among chimpanzees than among any group of humans observed by anthropologists. Wrangham (2017), “Two types of aggression in human evolution” https://www.pnas.org/doi/10.1073/pnas...

*Increasing hominin intelligence and enhanced social skills probably took proactive violence to a more lethal level. As hominins continued to evolve during the Pleistocene, they developed language skills, began making more sophisticated tools, and learned to control fire. But our hominin ancestors brought their chimpanzee-like propensity for proactive violence along with them – and made it more deadly with spears, axes, and arson.

*As our ancestors gradually evolved into modern humans, culture grew increasingly important. And when human populations started expanding into new parts of the world with more varied environments, cultural knowledge about food sources, terrain, and climate became crucial to survival. Henrich (2015), _The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter_
https://www.amazon.com/Secret-Our-Suc...

*As humans fanned out around the globe, separate groups began to develop unique cultural practices that differentiated them from others, adding another layer of complexity. Humans, like chimpanzees, are tribal (and quick to see other groups as rivals). But our greater cognitive ability and our evolutionary history of cooperative group living have enlarged our parameters for both fighting and cooperating. Human capacity for group identification probably far exceeds that of any non-human. Studies suggest that, especially under stressful circumstances, individual identity can “fuse” with group identity so strongly that individual and group virtually become one. Shared initiation rites and shared combat experience seem particularly effective at creating this fusion. Whitehouse (2024), _Inheritance_ https://www.amazon.com/Inheritance-Ev...

*Identity fusion may explain an evolutionary paradox of war: Why do soldiers risk their lives for country or ethnic group? Dying prematurely in battle seems to make no evolutionary sense on an individual basis, especially since many warriors are still too young to have children of their own (so their genes die with them). Identity fusion suggests an answer. Some fighters who have shared deadly combat report feeling closer to their comrades in arms than to their own families.

*Put this all together and a picture starts to emerge: By the time hunting-gathering humans took their first steps toward sedentary living and civilization, they were already loaded for bear. Hunter-gatherer tribes still mostly practiced coalitional violence in forms not too far removed from those of chimpanzees (raids and ambushes on rival groups). But as tribes grew into chiefdoms and then states, warfare became increasingly organized. And increasingly predatory as societies accumulated wealth -- and grew large enough to encroach on one another.

Caveat: All the sources cited here have their critics. And science is an ongoing, iterative process. New data may come along to change some or all the conclusions noted here.

[Alessandra De Vito · Rating 2 out of 5]

This was fine; I felt that this was more a list of facts one after the other rather than an analytical deep dive. would have been more interesting for me if the author went much more in depth on one or two examples rather than listing off example after example/small anecdote after another. Perhaps my expectations were a bit skewed though, but this wasn't my favorite book on this topic.

[Aaron · Rating 4 out of 5]

There’s an obvious reason why people get angry and bash (or try) in the heads of the subjects of their ire and a slightly detailed look at the phenomenon. What we get in “Why War?” is the latter. Written by someone who has spent nearly their entire life writing about probably the biggest conflict “why war?” has ever been questioned about, WW2, takes a step back from his normal focus to instead zoom out and engage the entire phenomenon of head-bashing over the ages from a little over half a dozen angles. Thus, not a book about the reasons why specific conflicts began, but something all the more interesting and dare I say challenging: warfare and humanity from caveman times to today, how come?

And perhaps just as important: can we throw a wrench in the seemingly never-ending cycle of violence? Do we know enough now to avoid all-out worldwide conflicts or is the “peace” we’ve seen since WW2 only masquerading the bombs forever cocked and ready? (Answered more or less in the book’s final chapter and conclusion)

That each chapter covers the “why war?” angle from various perspectives that give us more of a dry bird's-eye view rather than from on the battlefield, it may be tempting to turn this review into some sort of armchair historian (barely, to be honest) low-grade cliffnotes where I take time to note observations for each part. I’m going to avoid that path, but I can’t entirely not note some of the really interesting things brought up in this well put-together book even the layperson can enjoy.

For example, in the second chapter, Psychology, contains some keen observations more salient now in our era of extreme consumerism than in the past: boys maybe for biological reasons (also covered some in Biology, the first chapter) like fighting and wars so guess what kind of toys and video games remain most popular? It seems like me being the only kid on earth who bought the SNES core system back in the day so I could get Sim City instead of Super Mario was an exception. We also see how in-groups create out-groups and how that leads to discrimination and later dehumanization (Nazis vs Jews and Hutus vs Tutsis were mentioned) and then there was the subject of mutilation of ‘less than human’ foes. A letter opener made out of the arm of a Japanese soldier was a thing, but one out of a German soldier?

And there’s more—a lot of it. The most obvious of course is the one-two punch that is Ecology and Resources (coincidentally, the chapters that follow our previous one). We engage in warfare not for the sake of bashing heads, but out of necessity, desire, and the sheer need to ensure food remains on the table—our table, not the other. An eye-opener yet obvious and explained oh so well. The 20th century in particular—the forte of our author—saw much strife regarding the latter (African campaigns in WW2 after all had a heavy focus on claiming land for agricultural expansion), but now more so with all out battles decreasing, the increase in that former strife may be returning with a vengeance due to climate change, a major factor not just now, but as noted in our book, in the past—the distant past as well.

Deep in Power, the penultimate chapter, we get a zinger of a quote that I feel sums up the most major pitfall of war quite succinctly: “Power exploited cynically by leaders to wage war in the name of a providential mission is the most dangerous and unpredictable cause of war from the classical world to the 21st century.” This, a chapter that focuses on three of the biggest names in world history that combine a cult of personality to conflict at all costs is preceded by Faith, a great read though probably covers subject matter most are familiar with (think Crusades and Jihad).

When I mentioned I was going to be reading a book by Richard Overy, a friend asked “so which war does it cover?” The answer, as we see, is all of them. And then some. “Why War?” nails its intent: to be a guide even for non-history buffs like myself to be able to digest and gain understanding on why groups of people sometimes do pretty bad things to another. Sometimes it’s for land, sometimes its for religion, sometimes Security (the last chapter), sometimes because it’s just getting too darn hot, sometimes because they need a warm water port, and sometimes to simply conquer for the sake of conquering. The allure of planting a flag, claiming a territory, and looking at a map of one’s own country growing and growing at the sake of anything else can be seen as an analog to a billionaire drooling over their ever-increasing bank account balance while the poor suffer out on the battlefield often dying for another’s cause.

[Tim Pendry · Rating 4 out of 5]

I have to admit that I was more than a little disappointed with 'Why War?' if only because I have enormous admiration for Richard Overy's work on twentieth century warfare and political history. His 2021 'Blood and Guilt' (reviewed elsewhere on Goodreads) is quite simply masterful.

In this book, he moves from the particular (his area of strength which is the period leading up to the Second World War and that war itself) to the general - an investigation into the phenomenon that is war. The obvious question is whether it is an avoidable part of the human condition.

No one can expect him or anyone else to come up with a definitive answer to that question so that is not the cause of disappointment. My own view is that there is something inherent in the way we have evolved as a species that drives us to conflict. We evade thinking about our own nature out of horror.

What is disappointing is only that Overy's natural and correct caution about making statements that cannot be clearly evidenced results in his own evasion of the ultimate question, not from weakness but because he cannot make the leap into some judgement of causes that will frighten the horses.

What we get is still useful - a detailed collection in a themed way of all the possible explanations of our propensity to war: biological, psychological, anthropological and ecological and, then, as a result of resource competition, ideology, will to power and concern for security.

Nearly all these 'causes' are plausible. A case can be made for all of them as at least part of the problem if not as the entire answer. As his narrative (or rather set of summaries) unfolds, it becomes clear that he can find no single cause in any of the disciplines he reviews.

This leaves us with a terrible gap - no clear single explanation or system of explanation and yet war happens and happens over and over again. It is happening now. Overy cannot make the leap into a speculation that might move us forward by shaking us up into questioning our own condition.

We cannot object to the general air here of implicit hopelessness. A multiplicity of explanations is no explanation and yet everything ultimately has an explanation in terms of cause and effect. Why are we so blind as a species to this particular phenomenon's nature?

Could it be that understanding the phenomenon might be more than we can face not so much about ourselves (although there may be an element of that) as about the species, the 'humanity', into which we have been born with little choice in the matter.

If war is an eternal, and perhaps will eventually be taken by us to the stars and far into the future, what does it say about us and our 'human essence'? War challenges our own utopian ideals and what passes for 'spirituality' and the beneficent universal that drives so much self-belief.

My suspicion is that war and the utopian 'othering' of ourselves are intimately related so that warfare centred on the clash of beliefs or ideals has a logic of its own especially where the clash is between people who claim, with apposite human irony, to represent some idea of peace or stability.

I certainly do not have the answer although I have suspicions emerging in my mind derived from the absurdity of our species and so of myself. This book will not open the necessary door but what it will do (reasonably effectively) is show us all the reasons and excuses that permit our ultimate evasion.

The origins and practice of war are likely to be understood eventually not through all the various academic disciplines whose theories are summarised so effectively by Overy but through a deeper philosophical investigation of what it is to be human.

I doubt if such a philosophical understanding will ever end war. Philosophy can change the forms of culture but not the species itself. Understanding ourselves and our species is not a positivist or academic exercise but is rather an acceptance and a detachment of some kind.

The best we can expect is that those who come to understand not war but our condition as a species that engages in war will learn both how better to survive as themselves and those they care about and play a role in mitigating the inevitable and the repetitive more generally.

It could be said that Overy does us a great service in laying out all the theories and concluding that they have not provided a definite answer. He is not a philosopher. It is understandable that he baulked at attempting a final explanation. The void he leaves is now clear enough to permit a filling by others.

[Steve Kohn · Rating 5 out of 5]

An eminent historian breaks down the main reasons humans go to war.

He may be a great historian but he's a difficult writer, with most pages holding only one paragraph and most sentences three or more lines long.

That said, it's worth the slog. Having read the book, we view our world with a sharper focus.

For example, we are familiar with warfare in the past few hundred years, mostly in Europe and the Americas, but this book reminds us of warfare in the New World. It was never good to be among the conquered, often resulting in slavery and thousands of human sacrifices by Aztec, Maya and Inca "civilizations."

In the discussion of slavery, we are reminded that it, and scalping, were common in North America before the white man arrived.

The author lists eight main reasons we go to war, and devotes a chapter to each. They are:

1. Biology. It's in our genes.

2. Psychology. "Because humans act consciously rather than from raw instinct, the biological imperative to fight when needed was reinforced by an evolved psychology that divided the human world in 'them' and 'us,' justifying intra-specific killing while creating a psychological predisposition to accept collective violence as a normative social responsibility, particularly for men." -- Page 227.

3. Anthropology. Go back as far as you want, and wherever you want, we've been at war.

4. Ecology. "Changing climate, either long-term transitions or short-term climatic shocks, has contributed to ecological crisis in obvious ways over the millions of years of hominin existence: a long decline in temperature combined with greater aridity could undermine the availability of staple foodstuffs, reduce areas of woodland and tropical forest, expand grassland, and change the distribution of local fauna; alterations in monsoon cycles could produce devastating floods and destroy the riverine environment; melting ice from glaciers and the two poles could cause a significant rise in sea levels, inundating coastal lowlands or covering over land bridges inhabited by farmers and hunter-gatherers." (Yes, one sentence.) -- Page 99.

5. Resources. Self-evident.

6. Belief. Not just religious, of which we know countless examples, but also includes the West against Marxism (Korea and Vietnam).

7. Power. Ancient Rome maybe the best example. Also, and briefly examined by the author, Alexander, Napoleon and Hitler.

8. Security. "The Correlates of War project shows that 80 percent of interstate wars fought since 1815 were between neighbors with a common boundary; the figure for 1648-1814 is 91 percent."

What I liked best were the many examples from around the world and from pre-history to the present war in Ukraine.

The book contains not a single map or illustration. It's helpful to have some knowledge of history and geography before starting this trek.

"Theorists explain what historians know: War is normal." -- Kenneth Waltz, 1989

[Greg Talbot · Rating 2 out of 5]

Since time immemorial, war has been a feature of the human race. As Richard Overy describes in “Why War?”, cranial trauma and bone fractures from war are present from the pre-domination era of homo sapiens (Pleistocene era). Bloody in tooth and claw across history, but the great hope, from messiahs to world leaders, is to build the coalition of peace necessary to end all wars.

Taking us through eight different scientific lenses (biology, psychology, anthropology, ecology, power, belief, resources, security) Overy takes battles across the historical timeline to build cases for roots of war. Multi-disciplinary perspectives, like evolutionary psychology built out some very strong web of ideas like a “warrior hypothesis” or perspective on “coalitional violence”, and fit into the biology/cultural models most persuasive today. Overy also looks at historical records such as the crusades, Napoleon's rise, or Germany’s imperil world wars to show the impact of power and belief on the psyche of a nation. Some of these ideas, such as Carl Schmitt’s idea of the “volk” or in-group aligned group, also build out coalitions and identity, in ways that are more nuanced than the assumed nation-state identity.

Although a short book, I had difficulties enjoying the read. It may make sense to chop up the chapter into scientific perspectives, but there were many times the narratives of battle and consequences was shorn with quick edits. Another recent book, “The End of Everything” by Katie Mack delivered richer narratives of battles and underlying motivations, that I found far more compelling. I also thought the questions asked by the public today about war never arose here. Questions about proportionality, drone warfare, deterrence, international coalitions (UN; NATO) , misinformation campaigns and social media never came up. It’s fine that the book was more focused on the past then current events. However, it would make sense to explore the framework on how war and modernity contend with war today.

There were certainly some interesting ideas here, but for all the density of the writing, it was very hard to arrival from the reading feeling more informed or confident about the fundamentals.

[Charles Reed · Rating 4 out of 5]

82 when we ask questions, like, why War, we really need to be asking other questions? Like, why not work As well? War physically is very expensive in demanding in this age. It is not economically Advantageous so Quite often it's much better to just spend money To get what you want because lives are expensive. You can frequently get what you want through other means much cheaper, Which is why War physically is an old man's game A lot of times. Now we do more other things like, uh, stock market Investments, Uh trades, Retail war, Advertising more Competition, The same thing, though Scarcity versus abundance. Is there a staircity of something? Do we want something from other people? Are people causing problems for us? There's so many different reasons for war.

And that's why physical an ideological. They both end up having the same Roots. Now, if we cover other things, We can look at this, even on a cellular level like, autophagy. Let's say I am. I'll look aside, And I'm finding, Uh, different cells that are problematic. Okay, There are weak. They are causing problems in the system. I start to attack this that cell. I break it down into parts. I use the better parts For other cells that are more deserving of it, Like meritocracy, type of thing That can be considered a part of war as well. Now you ask me personally. Why do I go to war? I do ideological wars Narrative Wars constantly because People act maliciously And next against my interest rate against my vision of the world. They end up holding us back, And that is frequently why I will do it. I will say that is immoral. That is dishonest That is unscientific. You are causing problems and hurting people. And that's why I go to war.

[Francesco · Rating 5 out of 5]

With an attractive question for title, the book doesn't have a straight answer. And rightly so. We fight for many reasons. Sometimes for some reasons, other times for others. Reality defeated every attempt to develop one universal theory of cause of war, and those who tried, ignored cases that did not support their theory. The book does a great job in summarizing the main streams of thoughts and research that throughout the decades have tried to answer this question. The first section explores the literature and research that point toward biology, psychology, anthropology, and ecology as causes of war. These are factors mainly explored through artifacts, arts, and historical documents and the author does a great job in summarizing a vast amount of knowledge with examples from prehistorical times to our age. The second part of the book focuses on resources, beliefs, power, and security as causes of war. Here, the author navigates from the Romans to Napoleon, from the pre-Columbian Mexican societies to Hitler, exploring the many factors that can lead to war. Even if in parts the book reads as a massive literature review, it is a great learning experience. Overy showed an extraordinary a capacity to bring together a huge amount of research in a coherent and readable way.

[Sun I · Rating 3 out of 5]

The author certainly has the qualifications and academic background to write such a book. Unfortunately, as many other reviewers have mentioned, this reads more like a comprehensive academic survey than a source of insights or thought-provoking ideas.

The book is split into 8 sections, each discussing one motivation (e.g. power, psychology). Each section does provide quite an in-depth discussion of the academic literature surrounding that motivation and some of the historical theories. Numerous and wide-ranging case studies are also discussed in each chapter.

However, the book fails to provide any overarching insights or synthesis of these ideas. It may well be the case that the author is simply trying to provide as factual a discussion as possible, but often the chapters end with unsatisfying and obvious conclusions (e.g. "Belief has never universally resulted in violence, but... it can be a primary driver that cannot by any measure be rationalized away").

I would recommend this book for anyone interested in the academic literature. But for someone looking for a better understanding and foresight into current global affairs, I'd recommend finding another book.

[Nico · Rating 4 out of 5]

The aim of the book is to try to give leads for the everlasting question as to "why war ?" or more so it could be renamed as "why human are so violents compared to others animals" in hope to give us the begining of an answer the famous millitary historian Richard Overy drew from others essential fields about the subject of human nature and the origins of societies such as primatology and anthropology. What I really appreciated about this book was Overy acknowledging the importance of biology and human "natural" evolution as to why we are so keen to seek large-scale violence and notably adressing indirectly the point as to why every societies in the world is in some sense patriarchal. While some parts of the book were clearly weaker than others and with some questionable historical interpretations (Overy is a WWII historian and it is shown) Overy managed to give a very concise and interesting perspective on the nature of human warfare and violence which reflect what I have already read on the subject such as "War in Human Civilization" and "Demonic Males" which are both cited in the book.

[Thomas · Rating 3 out of 5]

Overy has a total command over the history of WWII and the parties involved in that terrible conflagration, so it seems natural that he would have an answer to the question "Why War?" But he admits that there is no simple answer, so he does the next best thing and analyzes the contributing factors: nature, nurture, scarcity of resources, need for security, etc. He begins and ends the book by referencing the Freud-Einstein correspondence on the question, which is notable for Freud's identification of the "death instinct" as a primary cause. Overy is fair to each theory he describes, but he very methodically demonstrates that none of these causes is solely responsible. The book is not entirely academic in nature, but it is fairly dry, as a serious examination of this very serious subject is bound to be.

[Boaz Maor · Rating 3 out of 5]

War in general and violent conflict in a slightly broader sense are so prevalent in our lives and throughout history that they sometimes feel too natural, pedestrian, despite their immense horrific impact and often no value. This is why this book is so interesting. It follows an emotionless assessment of the history of and reasons for war. Such an assessment is valuable if we are to understand why wars occur and how to prevent them.

[Bobby Ramirez · Rating 4 out of 5]

Highly recommend this short overview of the historical causes of war, and why humans began organized violence in prehistory. It provides a realistic future outlook for what conflict will look like in the 21st Century and on, despite the idea that conventional war among great powers cannot exist in the nuclear age.

[Hanh Do · Rating 5 out of 5]

One of a kind. Each chapter presents one element, with in-depth explanation and vast amount of examples that helps to elaborate wars from the beginning until present time. Especially interesting how those elements support each other in a comprehensive way. Beware that the book consists of academics terms.

[Rong Wu · Rating 4 out of 5]

Why? Because it's there; much as Sir Hillary would answer ("about why climbing Mt Everest"). A better thesis might be "how not war?" For that, John Lennon had answered already: just "Imagine".
"Imagine there's no countries
It isn't hard to do
Nothing to kill or die for
And no religion, too"

[Keith Kelley · Rating 4 out of 5]

Very good overview of the subject, but a bit scattered and could use a stronger through line of some sort. Something like an estimate of the relative size of the impact of each factor at the end of each chapter and discussed in the conclusion would have gone a long way.

[Graham James Keddie · Rating 4 out of 5]

The author takes you on a thorough trawl through the various academic disciplines' attempts to explain the prevalence of war through the ages, and the.result is worthy of attention and respect, but I found it a bit too much tolike a 'book designed by a committee'.

[Berend Mets · Rating 5 out of 5]

Excellent question; well answered.

Richard Overy no stranger to the subject, has written and outstandingly researched, book on a subject that has excercised mankind. The fact that war is not only in our genes by for them and hence has a future is a great conclusion.

[April · Rating 3 out of 5]

All theory, but still interesting