Disclaimer: Most of this comes from either original research (cited as is), misc. knowledge from everywhere, or otherwise fun little anecdotes.
TL;DR VERSION: RICE IS KING. KENSHIN INVENTED ONIGIRI AND SUSHI. SHINGEN INVENTED RAMEN.
I think I saw a post earlier with someone going: what does people during this time eat. Then I realized something: the food habits of this time isn't very well documented at all. Just what did people eat? How did they eat? I figure the question's interesting enough to write this up.
First, let's get something straight here. This idea that we can eat as much as we want, when we want, and how we want? This is really a modern concept. Compared to today, what the people of Sengoku Japan (and, in comparison, almost everywhere else in the world) considered to be filling we'll see as diet food at best and plain starvation at worst. Japan, in particular, had a bit of a problem. Unlike its neighbors, Japan was mostly mountainous. This alone meant that production - an issue everywhere else - was going to be an even bigger issue from the start. Please keep this point in mind as you read on.
When you consider food, you realize that food itself was a huge motivator. Why did people fight in the Sengoku era? For dominance of Japan, yes, but also to get their bellies full. The army that is better fed will win more, perpetuating a cycle that continues on. Rice (こめ) is the quintessential crop produced mainly in Japan, yet, unfortunately, most of the poor farmers who cultivated will never get to eat the fruits of their own labor. Most peasants could not afford rice at the time, and instead, ate either a combination of wild wheat, oats, or the foxtailed millet (アワ. I will be using 'millet' to refer to this throughout this post).
While I am not going state that rice was in the exclusive domain of the warrior class, I would like to emphasize its rarity at the time. Evidence we can gather include a recruitment notice preserved in the Hojo family noting this as a perk for joining up, some diaries by handmaids (the one I cite, unfortunately, is in dispute because some scholars think that this work was composed much later in the edo period), and from personal writings and correspondence between a number of samurai and their family members. Ever seen the movie, "Seven Samurai"? That movie, while ahistorical (and not really what I want to use as a source , illustrates this point as well. Unfortunately, most of the bushi class at the time could not really pass up an opportunity to fill their stomachs - an advertisement stating that they can eat all they want is motivator enough. Let me insert another anecdote recorded in the History of the Hojo to show my point.
Before Oda wtfpwned Imagawa Yoshimoto at Okekazama, the Imagawa/Takeda alliance was attacking the Hojo Castle of Matsuyama, located in Musashi province. After many days of fighting, both sides were exhausted. The Takeda alliance, assuming that the Hojo must have been running low on food and water, sent scouts to check. What they found was extremely disheartening: soldiers were blatantly washing their horses on the most visible spot of the castle.
To the besiegers, this was extremely disappointing - the Hojo shouldn't even have water to drink and now they're washing their horses? In either case, the Takeda-Imagawa quickly called for a truce and began diplomatic talks. Matsuyama was attacked numerous times in history, and this battle ended in the castle being given peacefully to the Imagawa as a result of other concessions. It wouldn't be as hilarious if the Hojo commander's response wasn't recorded, though.
Takeda/Imagawa: How could you have water to wash your horses? We thought you were out of water two days ago.
Hojo: Yes. Yes, we were. I pulled a gambit - my soldiers were pouring rice on the horses to make it look like water.
Takeda/Imagawa: ...
Hojo (unrecorded. My speculation): (because your troops probably haven't even seen rice in large quantities before. Hurrdurr )
What I told sounds preposterous, doesn't it? Samurai and ashigaru unfamiliar with rice? If you think about it, though, it makes sense. There was no national-scale food transport or trade. There was little food being produced. Even in years of plenty most of the people still had to supplement their diet with whatever they could get their hands on. There was most certainly no importing of food from nearby countries either - food, as I stated, is an important matter. Certain provinces had it easier - Owari, for instance, had more fertile soil. Feeding its people wasn't nearly as difficult as say, Kai, which is why Takeda Shingen was nearly worshipped by his people. Before Shingen came into power, there were a string of poor harvests that lasted for five to seven years. Shingen's father, however, still insisted on making war. The fields were laying fallow and people were starving to death left and right. Shingen basically came along, promised people food, and took power. He would keep his promise quite well. Irrigation was improved considerably, and if you're interested there is quite a bit of research out there on the dams and various construction projects that he carried out.
But back to food. Usable land (arable, highly productive land) was scarce. There's a reason why these wars continued - one of the most useful things to pillage was food. Japan also didn't produce much in terms of livestock, and in most of the case, the cost to feed livestock was beyond the average peasant. Fish, while plenty, was not an option either. In most cases, the fish caught by peasantry is requisitioned as tax, so for the average peasant, even fish was considered to be a luxury.
So what about the samurai? There was little distinction in the diet of lower-class bushi, small land-owning peasants, and poor peasants. Only when we begin to reach retainers of a few thousand koku or daimyos do we begin to see some variety. For the average bushi it was largely dependent on where they lived. If they were near the seas, fish and other seafood was readily available. For the folks living in mountainous regions like Echigo, there were wild game that could be hunted - though such animals, inevitably, were fewer in number and it was neither a reliable food source nor a time-efficient one. Bushi living in provinces like Kai (again, poor Takeda. Which might explain why he had such a thing for tasty edibles) has neither access to sea nor easy access to wild game, so they were stuck either buying things from nearby provinces or stuck with fishing from nearby rivers.
This is not to say that there were no luxury foods during this era. I am not suggesting that every single bushi were malnourished or starving. I am, however, noting the atmosphere of frugality, and that there was simply not that many things to eat in the first place. If we look at the menu of Oda Nobunaga's feast after he defeated the Azai, for instance, we see venison, swan, wild boar, hare, and even things like squid and sea cucumbers. But unfortunately, not everyone is Oda.
Typically, for the poor of the Sengoku era, they were lucky if they had millet. Rice, as stated, was a luxury. In almost all cases, all of the rice produced was requisitioned by the lords. Japan at the time practiced something called 60-40 policy (I don't know the english term - that is my own translation). Roughly put, 60% was given to the daimyo, and 40% left for the people. This, however, do not account for the fact that their local lords or rulers or landlords may skim on top of it and add additional aspects of taxation. Furthermore, this taxation was assigned by person, by land, and production isn't always maximized. So, realistically, it was more like 80-20%, where the peasant got to keep 20% of their produced food, typically those on the lower value level like millet or wheat.
This effectively forces the peasantry to stick to things like millet, vegetables (generally whatever they can find), or radish. If you were lucky, you may have scraped together enough to buy something from the list below once in a while - but that was unlikely to be the case. Most of the time, as a peasant, you were probably thankful that you weren't starving to death.
A special note must be paid to the radish here. This thing effectively saved Japan. When the radish was first introduced, they were tiny - no larger than the length of your smallest finger. Through cultivation, however, they've increased in size substantially. The daikon is something that appeared in the table of everyone - from the emperor to the peasant, everyone ate it. It could be eaten raw, but is more frequently pickled into a sort of salty thing to give food more taste.
If you were a land-owning peasant (Kokujin) or a moderately ranked samurai retainer of some daimyo, on the other hand, there will be more variety on your table. We're talking about someone ... say, you were one of the Sanadas during Shingen's heyday. Common vegetables that your wife or sister may bring onto the table included the gobo (牛蒡), shiso (荏胡麻), Azuki bean (小豆), red bean, soybean and its fermented variant, natto (纳豆), konjac (蒟蒻), and the taro (里芋). Gobo is likely to be either pickled or served as the base for certain dishes. Shiso leaves could be eaten, but it is better known as a source for oil than food. Preparation for konjac and taro really haven't changed across the years, and the numerous types of beans (I've only listed three) can be prepared in a number of ways as well, even occasionally sweetened or serving as dessert food.
Forgot to mention. 鰯 - anchovy or sardine - is very common as a seafood supplement. It'll most likely appear as a heavily salted thing no larger than your fingers, used again to go with rice or millet. Natto was popular no matter where, though if you were from Echigo as opposed to say, Kyushu, the type that is prepared differs. One is heavily salted, the other, less so.
Konbu and nori (海苔) was common if you were near the seas, though nori was naturally dried on the rocks nearby and probably not the processed type you see during the late Edo period. Konbu, though, because it sounded like victory, was pretty much something you're guaranteed to see before you head off to battle and when you return. And, depending what's in season, perhaps eggplant (茄子 - these are much more narrower than the ones we are used to seeing), lotus, or cucumbers (both the 胡瓜 and the smaller variety) are available as well. For fruits, the ume (plum, though technically an apricot) and whatever fruit trees your lord may have cultivated was likely to be common if they were in season.
Rice, however, is probably still not something you have everyday. However, you do have ready access to buckwheat and millet. Typically, buckwheat at the time was not turned into noodles (more on this later), but rather rolled into balls and steamed or roasted.
For something more luxurious, the shrimp (海老 - this was period appropriate. That term was a loanword from China, basically), hyou-butsu (表物. This is a period-specific term used to describe a mixture of other seafood goods, typically dried and placed into a mix of sorts), and mussels. Mussels are cultivated at the time, and fishermen may always get lucky and bring back something tasty, like tuna. Though tuna is far more likely to be turned into bonito than to be eaten fresh. For sweet things, sweet potato (唐芋), satsuma (蜜柑. A type of mandarin orange), grapes, pears, and peaches may also be in season, and would be available with some effort. The mountains of Kai, for instance, was known for its production of grapes that fetched for a substantial price anywhere.
You may have noticed that meats, strangely, is not on this menu. Buddhism-frowning-on-eating meat and Imperial-edict-prohibiting-the-eating-of-meat aside, meat was uncommon. Some people who were either exceptionally religious (many) or exceptionally traditional (read: the Imperial court) didn't eat meat out of tradition. For others, livestock was far more useful for their ability to tilt the fields, and to eat cattle was either a grave offense (if you were a peasant) or great stupidity (if you were a bushi). Chickens were also uncommon, and were mostly treasured for their ability to lay eggs. What was more common, as stated above, was wild game. The wild boar, in particular, is relished by daimyo and peasant alike. (There was a popular story regarding our favorite Dragon of Echigo [Yes, there were more than one.] Kenshin, in particular, called it "mountain whale" (山鲸). The rationale was that it was now a whale, and thus, he could eat it with impunity.)
Things like pheasant, hares, and foxes are also popular, with the singular most well-known Sengoku-era dish being the salt and peppered deer (recipe I will attach at another post if anyone's interested in. The reason why I make this claim is that this dish seem to appear all over the place, and a number of daimyos were known to have favored it).
Nonetheless, food was still scarce. For the poor, it was what you could get. Even for the better-to-do it was typically divided into tables. As a bushi, you would receive your own portion, typically composed of a bowl of rice, a soup of some sort, and three side dishes. Normally, with the exception of weddings or great feasts, fish or shellfish will not appear at the same time. Even then, the fish and shellfish are typically in small quantities - only enough for a few bites. This was ubiquitous around the time, perhaps due to the Buddhist influence that frowns upon excessive consumption.
Furthermore, bushi as high-ranked as a joushi (think of these as one step directly below the daimyos that spanned multiple provinces like Uesugi Kenshin) were often recorded that they went out onto the fields and did work alongside the men. This wasn't something they were doing for PR. It was for sake of survival. Their wives would often take the other women into the mountains to seek wild vegetables as well. If I haven't hammered in the point that food is important and food is scarce, I think I may be getting my point across.
Speaking of consumption, the people at the time typically only ate two meals. In the olden days, it was reasonable. Production was poor, there wasn't nearly enough food, and if one skips dinner and go to bed early, no one'll feel hungry at night. They cannot skip breakfast or lunch because they needed strength for work at the time. This habit, as unusual it may be to us, is practiced by basically everyone - from the shogun to the peasant.
Though, of course, due to the nightlife of higher-class bushi being a bit more common, most of the famous figures do appeared to have eaten dinner in some way. This is evident due to the numerous anecdotes found in numerous personal biographies of daimyos regarding favored night-time snacks or "can't sleep, was hungry, wandered outside and found incident X!"
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In either case, rice was the quintessential food for the bushi and anyone who needed to fight. Unlike the neighboring Chinese or Koreans, whose supply units carried a significant amount cooking utensils such as pots and pans, Japan was again, mountainous. Whatever was easy would be best, and that is why "riceballs" became the de-facto food for an army on the move. The paradigm was to carry as little as possible.
The biggest advantage of rice was that it is easy to carry, easy to eat, and relatively resilient to spoiling. Hungry soldiers needed no knife or fork or chopstick to eat a riceball, and they were stupidly easy to make - the term "rice ball" is exactly what it says on the tin. Generally, these balls are made by either the soldiers themselves or the ladies in the household. Something quite well documented is that the finished products would be wrapped around by a layer of light cloth and knotted with many knots. Each "knot" would contain a ball of rice, which was supposed to sustain the soldier for one meal. Typically, two riceballs would be a day's meal for the soldier. This type of rice belt, known as Koshibin (腰便), was very convenient, though each soldier could probably carry no more than ten day's worth. Salt would often be added to the rice for taste and for preservation purposes.
It is important to note, however, that these rice belts are personal rations. Something that many sources fail to note is that the daimyo or joushi are also responsible for the larger-scaled supplies. Typically, again, the lady of the household with her maids are responsible for this. Again, rice is produced in a large scale, wrapped in clean sheets woven from reeds or dried hay, and carried on supply carts nearby. They also had to process raw rice, in case the battle was going to be long and the troops did need to cook in the field. Though, by the time the taisho has ordered a break, most soldiers are probably too exhausted to cook anything. Instead, a popular "cooking" style for the soldiers at the time was to bury the rice in something non-flammable, put it underneath the fire, and then retrieve the rice when it was hot/slightly scorched.
Some of you may be wondering: wait, even soldiers are only given two meals a day? Wouldn't they be hungry in that case? The answer to this was that apparently, two was enough. Military historians have a number of explanations, ranging from short combat distances to high caloric density in the riceballs. Your guess is as good as mine.
Of course, rice isn't the only thing that kept the soldiers fed in times of war. Umeboshi is popular even to today, and it often accompanied riceballs in an ashigaru's meal. Popular condiments at the time included all kinds of pickled foods including umeboshi, salty seaweeds like nori or konbu, salted fishes of all sorts and of course, miso.
The first two I do have some special commentary on in large part due to Uesugi Kenshin. Just remember, however, that with the exception of what I describe above, the normal ashigaru likely will have to make do with what they bring from home - condiments and side dishes like the above are usually reserved for generals and samurai retainers. The common ashigarus, however, would be pleased to no end at the fact that they'd be able to eat their fill of plain rice.
Kenshin himself was a fan of the ume, or Japanese apricot (I will also refer to it as the plum), and he came up with an idea as he was eating lunch one day. Umeboshi, or pickled plums, is a sort of brined salty/sour thing that is still commonly eaten today. Now, what Kenshin figured was that umeboshi could be easily mass-produced. If he ordered his cooks to place an umeboshi in the center of every riceball, then the flavor of the umeboshi would drain out into the rice as they go on the march. Kenshin, being the man he is, tried it on his own lunchbox at first (There is a popularized eating utensil at the time termed menoke, which could contain roughly the size of a riceball (about 200-300g) - think of this as just some sort of container), and ...
Well, he liked it. He gave it to his generals. They tried it, and they liked it. The full version of this story is recorded in the History of the Uesugi, but all we have to know is that soon after, the standard-issue meals of the Uesugi clan soldier became this: a single ume will be added to the center of any riceball.
Of course, the soldiers liked it much better than plain white rice. Kenshin himself was also fond of eating simply, and it is recorded that this was what he brought as he rallied the Kanto daimyos to attack Odawara castle. This will eventually form the basis for our modern day Hinomaru Bento (日の丸弁当). Being a biologist myself, there are scientific studies that has shown the effectiveness of umeboshi at killing certain common harmful bacteria, including e. coli.
There is another story, too, regarding Kenshin wrapping rice in nori. If that is true, this would imply that Uesugi Kenshin invented sushi. Actually, wrapping rice in nori was common practice at the time, as nori is naturally tasteful due to the lingering sea-salt still remaining on the seaweed (recall that nori is dried naturally), and it could be eaten alongside the rice for additional flavoring. Whether or not Kenshin invented sushi is a debate we should save for another day.
Not to be outdone by his rival, Takeda Shingen also had his own unique food attributed to his invention. The answer may come as a surprise to you: noodles.
Think about the battle of Kawanakajima for a moment. This battle illustrates the timeframe perfectly. The battle lasted from 7:30 AM all the way into the afternoon. I don't think any of those folks had time to eat lunch in between - though they may have had time to sneak a bite in here and there if they were lucky. While the Uesugi samurai had their Hinomaru onigiri, the Takeda had noodles. For all intent and purposes, Shingen invented ramen - a type of noodles meant to be eaten rapidly, pressed, is light to carry, and required little more than a hot pot of water.
For referential purposes, noodles were not brought to Japan until much, much later. What were around, however, was a type of noodle called 馎饦 (hoto). Preparation was pretty ridiculously simple, too. You made dough. You sliced it into noodle-sized pieces, and then you cooked it. Again, it was very convenient as military food. All the hungry warrior had to do was to carry around pieces of dough (which can be eaten raw if necessary), shave off pieces into a pot of hot water (not difficult to find since they had to water the horses), and then scrounge up whatever else pickled vegetables or things they could find.
Takeda Shingen, in particular, enjoyed these hearty noodle stews. It is recorded that all of the Takeda supply forces had with them a ready stock of miso - perhaps for the exact purpose of flavoring these noodles. The miso, in particular, was fermented using a secret recipe (that is, ironically, recorded in the Koyo Gunkan - though I strongly recommend you just buying "white miso" in an Asian store. My own attempt [mostly for the lols] ended in very miserable, shameful dispray). Supposedly, it not only was delicious, but it also relieved symptoms of stomach pains and replenished energy. This would be divvied out to the troops in small portions and intermixed with their dough in some arcane manner. The result was something that suspiciously looked like the insta-soup stocks found in our ramen noodles today. Nonetheless, this was another instance where the troops loved it.
While I personally suspect it was because miso had to be prepared hot, and hot food for tired samurai = panacea, I would personally not be surprised if Shingen would claim that his miso could cure cancer were he alive in our modern times.
The Takeda forces also carried with them a sizable amount of pickled vegetables of all sorts. Shingen believed that having additional variety would be healthful and good for fighting. For comparison purposes, I attach Shingen's own lunchbox in comparison to Kenshin's.
Spoiler Alert, click show to read:
... Ok. So that wasn't what Shingen actually ate. Anyways, you get the idea. Speaking of these bento boxes. Bentos existed in the Sengoku era. In many cases, the samurai would have their retainers make their own bentos and fill them with all sorts of goodies to distinguish them from the common ashigaru. So it is conceivable that Shingen may have had something that might have looked like this, but I highly doubt the Takeda mon would be engraved on the food itself.
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Right. Let's move away from samurai for a second and look at monks, since the DLC is coming out soon enough. No matter the Ikko Ikki or Shinto Buddhist, they typically stuck to a rigid vegetarian dietary habit. Unfortunately, there is little recording of what they may have eaten, though we do know that most of their food was noodle-heavy. Udon existed at some point before the Sengoku era - or else Nobunaga would not have been fed Udon with tofu when he visited Seidai temple. We also know that there was a type of oily tofu flavored with miso, and that it was a common occurrence for the monks at the time.
This heavy reliance on flour is probably because rice was requisitioned by the daimyos.
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Someone down there asked about liquor. Sake was indeed what they drank at the time - though it is considered to be the lighter (せいしゅ) variety. Then you have Nigori, which was a sweeter, more alcoholic, and generally a cloudier look alcohol than the other. Liquor, of course, was considered to be a luxury at the time due to the scarcity of food.