Strangely enough, archaeologists have yet to turn up any evidence of battles or wars. Ten thousand years is of course a long time for uninterrupted peace but most experts believe that on the whole the Jomon people were hunter-gathering tribes because:
1. There have been no signs of walled settlements, defences, ditches or moats.
2. No finds of unusually large numbers of weapons such as lances, spears, bows and arrows.
3. They have found no evidence of human sacrifice nor masses of unceremonially dumped bodies.
Nevertheless, there is evidence that from time to time disputes broke out or acts of aggression occurred, beginning as early as the Initial Jomon period where remains of a male individual with a hip bone perforated by a bone point Kamikuroiwa Site has been found. Arrowheads were found in the bones and broken crania. There are many examples in the Final Jomon Period.
Heritage of Japan 
We have plenty of archaeological evidence indicating that war was not a significant or institutionalized activity among the Jomon people. For one thing, there are no weapons specifically designed to kill human beings. There are hunting tools like bow and arrow with stone projectiles – which, of course, can also kill humans – but there are no swords, no shields, no helmets, no armor or other combat gear, no pictures or sculptures recording battle scenes, no monuments to glorify warriors, no man-made structures that even remotely resemble a fortress or garrison, no walls that meander across the surface of the earth. Jomon people never developed the concept of a political state, nor did they have a concept of education. Children grew up by simply imitating the adults, persons who were at once self-reliant individuals and cooperative community members. Their economy did not require collaboration of more persons than there were in the local group, and the principal occasions for members of one group to meet those of others were centered around trade relations, intermarriage, and perhaps festivals. Their egalitarian society was based on matrilineal extended families within a tribal network (as is typical for many Neolithic cultures throughout the world). Agriculture had not developed beyond little gardens and so there was no need to fight over land or resources. They left behind the works of a rich material culture characterized by proliferatingly decorated pottery, terracotta sculptures, and stone circles. This was possible because they lived by what we call a “Paleolithic Rhythm”, meaning one or two days of work for living followed by two or three days of leisure. This in turn means that their natural environment was fairly rich in food and other basic resources to satisfy their needs and many of their wants (if people have to struggle hard for daily survival, they simply don’t create much of a culture).
according to Sahara Makoto there were some state like structures by the end of Jomon
There are signs of social stratification and existence of very large village settlements, large-scale industry, and since the Jomon’s existence has been one of the most enduring cultures in the world, one wonders if it might be more properly be called the Jomon civilization instead of merely the Jomon Culture. Sahara Makoto is according to Charles Keally, “There are about 6,000 to 7,000 archaeologists in Japan. Sahara Makoto is one of the top 10, one of the top 0.2% of Japanese archaeologists. …An elite academic, such as Sahara Makoto in archaeology, cannot be imitated and certainly cannot be faked. Elite academics are first of all elite humans. The “elite” is something that comes from the heart, and that reflects the heart as much as or more than the academic.” http://www.t-net.ne.jp/~keally/Reports/SIR2006/sir2006.html
it is important to note that we can speak of state-like structures/civilization when we consider only late Jomon (Kamegaoka period) while incipient/early and middle Jomon was not civilization.
Mr. Yokota begs the question a bit by substituting technology for intent. War can be satisfactorily waged with bare hands.
While it’s true that war can be waged with bare hands, it’s not likely because it would have been an inefficient method counter to the survival instinct. Since man had long been used to fashioning sophisticated weapons for catching game and defending himself from predators, it is likely that in warring with other humans, they would have employed the same sophisticated hunting technology available. Blow-darts have been found in southern Japan, harpoons in eastern and northern Japan, knives and arrows were available in the Jomon era, why would they not have used all of their offensive available weaponry in warfare, had there been wars?
Isn’t it Manatagwa man who is the first pre-Jomon fossil in the islands? 6 individuals with Jomon-like knocked teeth that show signs that they were cannabalized?
“but there are no swords, no shields, no helmets, no armor or other combat gear”
Well…of course not …metal had not been invented yet. There are mass graves of people who were murdered in Egypt long before walls or swords or armor.
The Minatogawa man is from the Paleolithic, and the knocked out teeth has no bearing upon cannibalism, but upon well documented rites of passage/group identity. That cannibalism occurred here probably can’t be ruled out for certain, but the literature suggests that most acts of cannibalism aren’t acts of war, but ritual acts of sacrifice or mortuary practices and I recall that one scientist dismissed the cannibalism in the case of Minatogawa because you should have been able to discern evidence such as signs of the bones having been scraped (as opposed to the two small hole punctures which could have other explanations). Judging from history, cannibalist acts by headhunting tribes were, however, common in this part of the world – eg., among the Taiwanese abor. tribes (Bunun), the Austronesians…the Iban, Dayaks, Bornean, Papua New Guinean and mostly Melanesian tribes(Korowai – K Y-DNA haplogroups). And since blowdarts have been found in the southernmost part of Japan and Japanese share some haplogroups in common with island or mainland Southeast Asia, it is not inconceivable that there may have been some low-level headhunting or cannibalism at work. Should one have to speculate on the provenance of such practices, I would look to the O3a3b-M7 (Japanese belong to the subclades) as a possible source of cultural diffusion of such practices. The existence of Mon-Khmer-Hmong close genetic ties was recently established: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0024282?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+plosone%2FEvolutionaryBiology+%28PLoS+ONE+Alerts%3A+Evolutionary+Biology%29 . And the fiercest headhunters in the world are said to be from the Yunnan or Shan region, the Mon-Khmer headhunting tribes of the Va/Wa (see TIME report – http://www.time.com/time/world/article/0,8599,2056076,00.html), Kachin peoples (although these also primarily belong to O1 haplogroups (which are not found in Japan). I would perhaps entertain the idea of new arrivals from SEA-of the Mon-Khmer tribes as a possible reason for the escalation of violence during the Yayoi period. Obayashi’s paper on the Myths of Wa points out a few similarities between the mythical traditions (cave/naga/primordial pair) of Japanese and those of the MK Wa/Shan tribes http://hermes-ir.lib.hit-u.ac.jp/rs/bitstream/10086/8490/24/HJsoc0030100430.pdf Those tribes would put up skulls alongside of animal sacrifices and libations to rice spirits. Overall, the genetic evidence puts the origins of the Japanese squarely with the northern Chinese, Northeast Asia, Buryats or Tibetans and of course the Koreans. While we’re on a roll in the speculation department, the Sumerians-Mesopotamians etc, Issedones and the Tibetans were supposed to have practised ritual cannibalism, the latter’s patriarchal family members eating the flesh of their elderly males and gilding the skull, so given the Tibetan-Japanese genetic connection, it might not be so far-fetched to believe that such similar practices existed in Japan. Nevertheless, hard evidence of cannibalism in Japan is still equivocal, scant or hard to discover, I have only seen one instance of severed heads lined up in a grave of a much later period
I can’t find any papers in English on rates of trauma in the Jomon period. Is there any data on that kind of thing, especially on trauma that might be violent?
I seriously doubt such data is available. Skeletal remains of the Jomon period are far too rare, given how far back it all was, and as the archaeologists are wont to explain … given how acidic the soil is in Japan. Even remains slightly nearer our own time such as Kofun era are pretty uncommon, with the rare (couple I think) finds from volcanic Pompei-like events that have been uncovered, and others from the cairns or passage tombs.
Returning to the original question of war and the aspect of “substituting technology for intent” (see above, haakondahl, October 30, 2011).
You cannot substitute technology for intent because it is an indicator of intent. Nobody invents a weapon of mass destruction if there is no intent to use it. In other words, if Jomon communities had needed or wanted to wage war against each other, they would surely have found ways and tools for more efficient killing and more efficient self-protection. However, this kind of “war science” remains unknown until agricultural civilizations were firmly established. Agricultural development makes it necessary to defend your plantations (and in some regions also precious water sources) not only against wild animals, but also against jealous neighbors and, if the occasion should arise, so-called barbarians who have retained a hunter-gatherer economy. This leads to the formation of a central, commanding authority supported by its administrative bureaucracy to organize and supervise a considerable labor force employed in civil engineering and the construction of a military infrastructure (fortifications, garrisons, logistics, arms industries, etc). The military becomes necessary also when additional territories have to be conquered for expanding cultivated lands – usually by waging war against the jealous neighbors or the uncouth barbarians. At this point you get – to use a political term – into the early stage of imperialism. This is a product of urbanization and urbanization becomes necessary to centralize the manufacturing process and the administrative structure. So you have a city-state. Now it lies in the nature of cities (as population concentrations) that they must take their food, fuels and raw materials from the surrounding “countryside”. To this end, the countryside has to be conquered, annexed, colonized and extracted from, thus creating the preconditions for institutionalized war. Jomon communities evidently lacked all these things because they didn’t even have an agriculture that went anywhere beyond some simple gardening, supplementary to their food resources, while heavily relying on hunting, fishing and gathering. Intent is motivated by need and/or want. Then comes the technology necessary to carry out the intent. In the case of war, the Jomon culture did not develop this technology.
While I think you have given a very good description of the pressures created by agricultural societies leading to ideal conditions for institutionalized war, the Jomon society already had sufficient conditions for war. They had bows and arrows, daggers and spears and were skilled users of those instruments which could have been used in battles against each other. Maps of Jomon settlements have shown there was considerable stresses on food resources in many areas as settlement patterns were dense during certain periods and in certain regions. The Jomon were not a pure hunting economy, but a semi-sedentary one, and more importantly, even based on hunting patterns, the hunting grounds within proximity of their seasonal settlements would have caused settlers to have crossed into each other’s hunting ranges a lot, hence, creating much potential for boundary disputes. We should have seen evidence of a lot of arrowheads lodged in skeletons or skulls, beheaded skeletons in the shellmounds, etc., had they been a warring-oriented society, but there is not a lot of it. When the Chinese described the commoners among the protohistoric period Yayoi peoples, they saw them as law-abiding and peaceful, it may be that it marks an overall character of the island peoples more similar to the Ainu and Tungusic or circum-Pacific peoples, that they were used to more cooperative sharing arrangements for living off the land, and for settling boundary disputes in a peaceful manner (we see a natural merging of Jomon pottery styles and lithics in regional hegemonic and geographic patterns over a long period) at least until the need to protect the later highly-stratified societies and fenced-off compound settlements of the Yayoi to Kofun-period settlements came about. We do not see this character with continental SEA tribal hunter-gatherers who were fierce headhunters with weapons like blowdarts.
On the other hand, it is interesting to speculate how the Jomon people may have changed with multiple waves of migrants into the archipelago. The Ainu are themselves descendants of both Jomon as well as post 11th c. Amur and/ Okhotsk peoples, and war historical and Ainu folklore accounts show the Ainu and “hairy peoples” to be fearsome warriors. I am particularly taken by this Ainu folklore that identifies the land of war to be The Heaven of Metal and the land beneath this one of fundamental rock (and source of iron) to be where wars are fought, and that this land in which they live called High Heaven (Takama) should be free of “spoilation”. Their god of war is the God of Thunder and rides a war chariot (which suggests a post-Jomon Bronze-Iron Age Eurasian-Scythian-style foreign ideology) see https://books.google.co.jp/books?id=vv1F3lKZE5AC&pg=PT43&lpg=PT43&dq=war+god+of+ainu&source=bl&ots=DylWTMy0Y1&sig=dUYK7hjMkuvvG_PG5UP90TTnsys&hl=ja&sa=X&ved=0ahUKEwj6j5_z-vHMAhXGMqYKHf1ED94Q6AEIKzAG#v=onepage&q=war%20god%20of%20ainu&f=false
The invaders came across the sea. With their advanced technology and overwhelming numbers, they quickly established a foothold, while the indigenous tribes of hunter-gatherers were pushed back, got absorbed, or simply perished. Sounds familiar, but this is not the European conquest of the Americas. It is what happened at the end of the Jómon Age, showing that the roots of Japan are much more shallow than was asserted by the history textbooks of our school days.
From around 400 BC, successive waves of immigrant-settlers arrived from the Korean Peninsula, which, by that time, had already gone through a historical process of kingdom-building (Gojoseon*) and agricultural development. Thus they brought with them new technologies – including but not limited to bronze and iron metallurgy, swords, halberds and other battle gear, irrigated wet-rice cultivation, domesticated pigs, and the hierarchical structures of a highly stratified society as it had been known on the continent for quite a while already. The ancestors of what later became Japan’s imperial clan were among them, and most likely of mixed Chinese and Korean origin.
By 300 BC, the invader-settlers from the continent had firmly established what today is called the Yayoi Culture. Yayoi settlements were large compared to those of the Jómon people. They featured palace-like residences for the ruling class, huge conference halls, and became increasingly fortified over the years – not only because they warred among themselves but also to keep the Jómon “barbarians” at bay, on whose lands they had encroached. Fortifications combined wooden palisades, watchtowers, moats, embankments, trenches, double-trenches, briar trenches, trenches with implanted stakes… considered all, these fellows certainly knew how to make war. Headless human skeletons like those unearthed in Yoshinogari are typical among archaeological finds of the era. The oldest recorded name of Japan apears in Chinese chronicles as Wō, mentioned in AD 57, when the Na state of Wō (centered around present-day Fukuoka city) received a golden seal from Emperor Guangwu of the Later Han Dynasty. (The seal was actually found in northern Kyúshú in the 18th century.) Chinese historians described Japan as a land of hundreds of scattered domains.
Prestigious goods and hi-tech commodities, imported from the Chinese Wei Kingdom (AD 220-265) to maintain the power of local Yayoi rulers, contributed to increasing hierachization among the statelets, eventually leading to domain expansion and the formation of the ancient empire. Its most significant material expression – the capital and the palace – was constructed by emulating the Chinese model. According to Chinese chronicles of the time, there was a Yamatai Kingdom, which had successfully unified the warring Yayoi domains and was ruled by Queen Himiko, who is said to have lived between 183 and 248 and sent diplomatic missions to China in the 230s. The geographic location of the Yamatai court was subject of debate by generations of historians and archaeologists. One theory focuses on the heavily fortified Yoshinogari settlement (33º19’25”N 130º23’26”E), but most Chinese accounts eliminate this possibility. However, directions given in these accounts are not always clear, with some of them ending up in the middle of nowhere. A more plausible theory puts Himiko’s court right into present-day Nara Prefecture – more or less around Sakurai (34º31’N 135º51’E). For one thing, this region corresponds to Yamato, heartland of the ancient empire and name of the imperial dynasty. It is also an area with a high concentration of kofun burial mounds, which, by the way, are similar to tumuli found in Korea. Travelers in those days might have, by ship or on land, followed the coastline of the Japan Sea for about 500 kilometers from northern Kyúshú to Izumo (35º22’N 132º46’E), which contains one of the oldest and most important worship monuments of the ancient empire. From Izumo, the traveler could continue his journey to Yamato, which would be a roughly 400-kilometer trip on modern roads. Yamatai might be synonymous with Yamato. The latter was written with different Chinese characters at different times. The official orthography used since the 8th century Nara Period translates as great peace or great harmony. Why not? After all, by subduing the Jómon-Emishi “barbarians” and unifying the empire, the general ideology of a Pax Japonica came into being.
In one of his essays, social anthropologist Koji Mizoguchi rejects the hypothetical prospect that Japan would have experienced the same kind of trajectory development if the archipelago had been situated in the middle of nowhere. The socio-technological complex based on irrigated wet-rice cultivation was necessary to initiate the shift from Jomon to Yayoi – the shift from egalitarian hunter-gatherer society to hierachical concepts of a political state.
* Gojoseon; the founding legend of the ancient Korean kingdom is recorded in medieval scriptures and begins with Hwanung (son of the Lord of Heaven) descending to Paektu Mountain (42º00’20”N 128º03’19”E, on border of present-day North Korea and China) to build a city. Eventually he meets a bear, turns it into a beautiful woman whom he marries, and they have a son called Dangun, who, around 2333 BC, becomes the founder of Gojoseon. Of course, this is national mythology, much like Emperor Jinmu of Japan, and while no evidence has been found to support it, the historical existence of the Gojoseon Kingdom was first attested in Chinese records of the early 7th century BC. It covered much of present-day North Korea and parts of northeastern China. It’s first capital was in Liaoning (today a province of China) and moved to P’yŏngyang (today capital of North Korea) around 400 BC. From the 3rd century BC, Gojoseon’s southern neighbor was the Jin State, which covered about two-thirds of the Korean Peninsula. Archaeological evidence suggests that its centers were based in the southwestern part of the peninsula, and artifacts of this culture were also found in Japan of the Yayoi era. Incidentally, the origin of the Dangun myth might be based on a forced integration of two different peoples: an indigenous bear-worshipping stone-age people, and an invasive heaven-worshipping bronze-age people with hierarchical structure. In this case, the latter would have come from northern China, as bronze was known there much earlier than on the Korean Peninsula. Incidentally, this would also be strikingly similar to the integration of the Jómon and Yayoi cultures in Japan: an indigenous animistic stone-age people (Aynu and Emishi were bear worshippers), and an invasive heaven-worshipping early-metal-age people (with Emperor Jinmu being a descendant of the sun goddess).
All this is great commentary, but it should be appended or addressed as commentary to the Yayoi Period sections.
With a vast majority of people being employed as peasants, the quality of life in general dropped dramatically during the Yayoi Period. Like elsewhere in the history of agricultural civilizations, it was basically the ruling classes which benefited from technological improvements, while ordinary mortals were a down-trodden lot, living lives far below the standard of hunter-gatherers. This cannot be otherwise because peasants had to drudge not only for themselves but also to keep the whole nation-state alive, including all of the rather unproductive men employed in administrative bureaucracy, military and military industries, and the manufacturing of luxury goods for the ruling classes.
This is partly also reflected by the pottery produced during the Yayoi era. It was wheel-turned and more functional than Jómon pottery, but lacked the aesthetic and artistic qualities of the hunter-gatherers. Thus it looks much like being made by people who had to overwork themselves to eke out a poor living. The wheel is the first tool in pottery aimed at speeding up the manufacturing process, and thereby also geared for serial mass production. Unlike the women potters of the Neolithic, much of the Yayoi pottery was probably manufactured by men. (Over the centuries that followed, the craft became increasingly dominated by men, some of whom were specialized artist-potters producing high-quality ceramics for the rich. We find these “potter-gods” still today, a few even designated as “living national treasures”, although the number of female studio potters has incrased rapidly during the latter half of the 20th century.)