I went to the Shingen-ko Festival in Kōfu because of a BBC documentary.
The programme was about the fact that the retainer families of the Takeda — a clan destroyed in 1582 — still exist, still know who they are, and still gather. That struck me as worth seeing in person. So in 2026 I went.
What I saw there sent me back to rewrite everything I thought I understood about a single sentence.
The line
A man in Takeda Shingen’s armor stands on a stage and shouts it. The crowd shouts it back. A sake cup is smashed. Then twenty-four generals in helmets come down from the castle with their retainers, are introduced one by one, and ride out through the streets while the town pours onto the sidewalks to cheer.
御旗楯無も御照覧あれ Mihata Tatenashi mo go-shōran are (mee-HAH-tah tah-teh-NAH-shee mo go-SHOH-ran ah-reh)
“Let the Banner and the Tatenashi armor bear witness.”
Some of the roles that year had been filled by open public application, and a group of young Americans — college students, a liberal arts program from what I could gather — were playing Katsuyori’s mother, her attendants, and several samurai. Wearing the armor is apparently the appeal, and I understand that completely. They were working hard at their Japanese lines.
I found myself wishing someone had told them what that sentence actually is. It isn’t a battle cry. It’s closer to a legal instrument — and knowing that changes where you are standing in that crowd.
The two objects
Mihata (御旗) — the sun-disc banner. Tradition holds that Emperor Go-Reizei granted it to Minamoto no Yoriyoshi during the Former Nine Years’ War, and that it descended through Shinra Saburō Yoshimitsu to the Takeda of Kai. It is kept at Unpō-ji in Enzan, Kōshū City, and is considered among the oldest surviving sun-disc banners in Japan.
Tatenashi (楯無) — formally Kozakura-gawa odoshi yoroi, kabuto, ōsode tsuki, a suit of armor laced with small-cherry-blossom leather. A National Treasure, held at Kanda Tenjin Shrine in Kōshū City. Tradition attributes it to Minamoto no Yoshimitsu, and the name is usually explained as meaning its wearer needed no shield. Shingen kept it at that shrine, northeast of Kōfu, to guard the demon gate; a branch family looked after it and brought it out when required.
Together they were the proof of succession. Whoever inherited the headship inherited these two things. Object and office were one.
So when the head of the house announced a final decision in council, he swore before them, and no further objection was permitted.
✦ Satoe’s Take: an oath needs a witness, and a witness needs a world
This is the same structure as swearing on a sacred text, except the witness is a family heirloom.
Mihata Tatenashi = the witness. The thing that sees the promise made.
An oath binds only where the penalty for breaking it can reach you. The penalty here was partly fear of divine punishment, but mostly this: the reputation of being a man who broke his word would follow you through every hall in Kai. As long as the Takeda house stood, an oath-breaker had nowhere left to stand.
So the object was never powerful in itself. It ran on a forecast that the community would continue to exist. End the community and the device ends with it — the object survives intact while the force drains out.
That was my reading. I had to revise it. I’ll come back to that.
The man at the center of the device
Takeda Katsuyori’s father’s line ran back to the Seiwa Genji. His mother was a daughter of Suwa Yorishige — the family that served the deity of Suwa.
So Katsuyori carried, in one body, both the bloodline the Banner certifies and the divine witness an oath calls on. He stood exactly where the two systems crossed.
And yet, alone among seven brothers, he was never given Nobu (信), the character the Takeda passed down through generations. There was persistent objection within the house to a man of Suwa blood inheriting it.
He was at the dead center of the device and never entirely inside the house. He is the one who ends up using it for the last time.
Was he even entitled to it?
There is a claim that Katsuyori had no right to raise the Mihata and the Tatenashi at all — that he was only jindai, a caretaker holding the position until his son Nobukatsu came of age.
The source is the Kōyō Gunkan, which reports Shingen’s dying instructions: conceal my death for three years, and let Katsuyori serve as caretaker until Nobukatsu is grown.
Current scholarship rejects it. Contemporary documents from after Shingen’s death refer to Katsuyori as the acknowledged lord and provincial governor of Kai. He was the recognized successor.
✦ Satoe’s Take
But look at where the judgments in this article keep coming from.
The unqualified lord. The most disloyal man in history. The mirror for samurai. The scene with the sword and the weeping hall.
One workshop produced the failing lord, the treacherous retainer and the martyr, all at once. Edo-period warrior society held that preserving and transmitting the house was the supreme virtue, and that destroying it was the depth of folly. That doctrine needed teaching materials.
And yet the claim was believed for four hundred and fifty years — which means that for four hundred and fifty years, the scene at Tano could be read this way: Nobukatsu had turned sixteen, and Katsuyori handed back what he had been holding in trust, exactly at the age when a caretaker’s term expires.
With no house left to hand it back to.
That, too, is a little too well made.
Honor or restraint?
✦ Satoe’s Take
Was Mihata Tatenashi an honor to Katsuyori, or a restraint?
Probably neither. It was all he had.
For a man of Suwa blood, the only brother of seven denied the Nobu character, who inherited over the objections of his own house, those two objects were the sole proof that he was lord. And they were also the measure he was held against — every time he raised the banner, he was compared to his father. After Nagashino especially.
Take them off and nothing remains. So they could not come off.
Then March. Kiso left. Anayama left. Oyamada left. They could leave. Each had land to return to, a name of his own, a self that existed outside the Banner and the armor.
Katsuyori alone could not. If he stepped outside it, he was nobody.
Five weeks
| Date (1582) | Event |
|---|---|
| Late Feb – early Mar | Kiso Yoshimasa defects; Takatō Castle falls (Mar 2); Anayama Baisetsu defects |
| Mar 3 | Katsuyori burns Shinpu Castle and withdraws |
| Mar 11 | Overtaken at Tano; Katsuyori, his heir Nobukatsu, and Lady Hōjō take their own lives |
| Mid-Mar | Takeda Nobutoyo killed at Komoro by Shimozone |
| Mar 24 | Oyamada Nobushige executed at Kai Zenkō-ji |
The order of events matters more than the list suggests.
Oyamada Nobushige is not “the third defector”
At the council in Shinpu Castle, Sanada Masayuki proposed retreating to Iwabitsu Castle in Kōzuke. The plan that carried instead was to enter Iwadono Castle in Gunnai — Oyamada’s country.
Tradition holds that Katsuyori, moved, gave Oyamada a sword and spoke to him, and that some of the men present wept.
Then Shinpu Castle was burned. Katsuyori destroyed his own fallback position. The column moved east. Beyond Sasago, the gate was shut.
Kiso and Anayama left. Oyamada invited, then closed — and it was his invitation that cost Katsuyori the castle he could have died in. The historian Hirayama Yū has noted that abandoning Shinpu is precisely why Katsuyori was denied an honorable death. For a warrior of that period, dying in your castle and dying beside a mountain path were not the same event.
✦ Satoe’s Take
I cannot verify the sword scene, and I think it should be doubted — it is too well made. A lord weeps, hands over a treasure, the hall is moved to tears, and days later that man shuts the gate. The story is engineered to make the betrayal maximally cruel.
The Oyamada memorial society itself states that the traitor verdict became orthodoxy through the Edo-period Kōyō Gunkan. If so, the weeping scene and the “disloyal man” verdict most likely came out of the same workshop.
Tano: the last use of the device
March 11, around eleven in the morning.
At Keitoku-in there is a pine called the hatatate no matsu — the banner-standing pine. Tradition says Katsuyori leaned the family banner against it and transferred the headship to his heir Nobukatsu before they died.
And the armor. Because Nobukatsu had not yet performed his first donning of armor, Katsuyori is said to have hurriedly dressed him in the Tatenashi, which was with them in camp, and then father and son took their lives. The armor was afterward carried back to Oso, buried for a time beneath a cedar at Enzan, and finally placed in Kanda Tenjin Shrine.
✦ Satoe’s Take
No castle. No council chamber. According to the Shinchō Kōki, forty-one men of samurai rank remained, and some fifty ladies-in-waiting. Lady Hōjō was nineteen. Nobukatsu was sixteen. Katsuyori was thirty-seven.
And there, beside a mountain path, he leaned the banner against a tree, put the armor on his son, and handed over the house.
He performed the full form of swearing before a witness, in a place where the witness could no longer reach anyone.
Katsuyori is said not to have raged when he learned Oyamada had turned. If he had raged, that would mean he still believed betrayal was something that gets punished. That he didn’t suggests he understood, before anyone else, that there was no longer any court to punish it in.
Going through the form while knowing it is void — that isn’t resignation. I think it’s defiance.
(Current scholarship holds that Nobukatsu had already come of age in 1579, which means this scene was probably constructed later. I’ve kept it anyway. That it has been told for four centuries is, for this article, the more important fact.)
“Please use me as your shield” — Komiyama Naizen
One man chased the column to Tano.
Komiyama Naizen Tomoharu was a hereditary Takeda retainer, one of the twelve tsukaiban. But at that moment he was under house arrest — he had criticized Katsuyori’s inner circle too bluntly, and after slander from one of them, his own lord had confined him.
He broke that order to come.
He was not of a rank to address Katsuyori directly, so he asked Tsuchiya Masatsune to carry the message. You may think me disloyal for defying your command. But for a hereditary retainer to be absent from the Takeda’s last battle would be a disgrace to the end of my line. Please use me as your shield.
Tsuchiya and others are said to have wept. Katsuyori lifted the confinement.
Then two things happened.
First, Komiyama learned that the men who had slandered him had already fled. The accusers ran; the accused came back to die. He is said to have grieved at this.
Second, he handed his mother, his wife and his children to his younger brother and had them taken away to safety. He deliberately pushed survivors outside the circle.
He himself died that same day in the fighting at Torii-batake. His memorial stone stands there still, and people go to it.
✦ Satoe’s Take
This is the answer I had been looking for.
How did an oath survive the death of the community that enforced it? Because someone deliberately arranged for witnesses to get out.
One account puts it plainly: it is because such people survived that Komiyama’s loyalty, Tsuchiya’s legendary last stand, and the Takeda heirlooms now held in temples near Enzan all came down to us at all.
The objects ended up in shrines for the same reason the stories did. People who knew they were finished chose which parts would not be, and pushed them out.
The device left the house
Here I have to correct myself.
I had assumed that because the device only worked inside the Takeda, Oda simply ignored it and won.
Oda did not ignore it.
The Shinchō Kōki, Kōranki and Kōyō Gunkan all record that Oyamada Nobushige presented himself hoping to enter Oda service, and that Oda Nobutada condemned him — to betray Takeda Katsuyori makes Oyamada the most disloyal man in all of history — and that on March 24 he was executed at Kai Zenkō-ji together with his mother, his wife and children, and others. Gunnai was left without a lord.
✦ Satoe’s Take
The winning side ratified the losing house’s oath and enforced it.
This is the hinge. The device did not die with the community; at the moment the community died, it went outside. What had been an internal reputation within one house became a formal verdict issued by the people who were taking the country.
That is why it survived four hundred and fifty years.
Why Anayama is disliked and Oyamada is hated
Anayama Baisetsu is not spoken of kindly either.
Shortly after the Honnō-ji Incident, having separated from Tokugawa Ieyasu, he was killed near Ujitawara — or by the Kizu River, accounts differ — by local villagers hunting fugitives. He was forty-two. The life he had preserved by abandoning Katsuyori ran out three months after the Takeda fell. His heir Katsuchiyo died in 1587 at sixteen, and the Anayama-Takeda line ended.
✦ Satoe’s Take
That is not a verdict. That is a story ending.
Killed by nameless men, house extinguished — it resolves itself. Well, of course. Karmic closure has no author you can argue with, but it also requires no appeal.
Oyamada’s case is different. A specific man, on a specific date, put a judgment into words. There is a text. Texts can be contested.
So the sanction that followed formal procedure is the one that kept the grievance alive. Anayama, processed by fate, needs no memorial society. Oyamada, handed a verdict, does.
And there is a tell. Anayama’s modern nickname in Japan is Ana-yuki — which is also the Japanese shorthand for Disney’s Frozen. He can be made into a pun. There is contempt, but there is enough distance for a joke. Nobody in Gunnai jokes about Oyamada. Four hundred and fifty years on and it still isn’t funny. That is the difference between being scorned and being stained.
The villain’s seat goes to whoever has no protector
There is an Edo-period reason as well.
Anayama went over to Ieyasu’s side and was brokered to Oda through him. Ieyasu built Keitoku-in at the foot of Tenmokuzan to pray for Katsuyori’s soul. For the Tokugawa regime, condemning Anayama outright would have been awkward.
Meanwhile the Kōshū school of military studies flourished under that same regime, and a story of collapse needs an exemplary traitor.
The seat that was open belonged to Oyamada. Gunnai had been left lordless, his family had been executed, and there was nobody left to defend him.
The villain’s role goes to the side with no protector.
The oath had a payroll
The Edo moral machinery did not only manufacture a villain. It manufactured a saint at the same time.
The late-Edo Confucian scholar Fujita Tōko praised Komiyama Tomoharu in the highest terms available to him — a splendid man, a mirror for samurai, one of the glories of the national history. Same workshop, opposite product.
And Komiyama’s descendants and relations are said to have been decently provided for through the Edo period, as the descendants of a loyal man.
✦ Satoe’s Take
This is what closes the argument.
The sanction of Mihata Tatenashi was never only about reputation. It was converted into employment and stipends.
A decision made in the mountains in 1582 went on being entered in household ledgers for the next two and a half centuries — rice for the loyal line, a lordless province for the other. The device survived not as morality but as economics.
And things that survive as economics do not disappear easily. When the crowd at the festival goes quiet for Oyamada’s banner, I think what we are hearing is the remainder of a four-hundred-and-fifty-year-old account.
What the memorial society cannot say
The Oyamada Nobushige Memorial Society states its purpose plainly: to clear roughly four hundred and fifty years of being known as the man who destroyed the Takeda. At its founding meeting it was reported that the Gunnai Oyamada family had been admitted to the association of Takeda retainer descendants. The central claim is that there was no betrayal at all — Sasago Pass was never blocked, and the troops were waiting at Ōtsuki as promised.
The society also says something else: that Nobushige saved Gunnai at the cost of his own life, that the Oda-Tokugawa armies never entered Gunnai, and that no resident, shrine or temple suffered harm.
✦ Satoe’s Take
Both claims are made. They sit side by side, and they are never joined.
The one line that would connect them — he paid the price of breaking the oath in order to save his people — is never drawn.
I don’t think it can be. Draw it, and the promise made before the Banner and the armor stands up and asks to be addressed.
The stronger defense was always available. The Takeda were not a modern chain of command; they were a coalition of kokushū, regional lords holding their own land, their own men, and their own obligations to the people on that land, bound by negotiated alliance rather than ownership. Under the ordinary logic of 1582, a kokushū had very little duty to march his whole domain into the fire for a dying overlord. Kiso did the same. Anayama did the same.
But that argument begins by conceding the departure and justifying it afterward — and the moment you concede, the question comes back.
What is being asked for is not a rational account. It is the removal of a stain. Those two requests cannot be satisfied by the same evidence.
Back at the festival
The twenty-four generals are played by local dignitaries — town mayors from the relevant districts, executives of Yamanashi companies.
But one of them, that year, was an actual descendant of the general he was portraying.
The cheer for him was noticeably louder than for anyone else. A descendant performing his ancestor, received with respect by the community. The same arrangement as four hundred and fifty years ago.
Oyamada Nobushige’s banner was there. Anayama Baisetsu’s banner was there. Both carried by people with no connection to those families. When they were introduced, the response was — I want to be accurate — flat.
Nobody organizes that. There is no rule about it. It happens every year, at a festival invented in the 1970s.
What was never said
✦ Satoe’s Take
What follows is entirely my own speculation.
Oyamada may have meant it at first. He may have ridden off intending to receive Katsuyori at Iwadono, gone home to Gunnai, looked at his own land and men and villages, and changed there.
There is some ground for reading it that way. The arrow-letter sent to Takatō Castle in late February claiming Oyamada had already defected is now regarded as false report — he had not turned then. Nor is it settled that he was the one who proposed Iwadono at all: the Kōyō Gunkan says Katsuyori’s aide Nagasaka Mitsukata argued for relying on him, while the Kōranki says Katsuyori put the question to him. He may have been volunteered into someone else’s plan.
And while Katsuyori waited at Komikai for the escort that never came, Oyamada first went and recovered his mother, who was being held as a hostage.
Komiyama Naizen also sent his mother, wife and children away to safety first.
The two men did the same thing. Both got the people they were responsible for out of the circle before anything else.
What differed came after.
Komiyama said his reason out loud. He asked for an intermediary, stated it before witnesses, and was heard. Tsuchiya wept. Katsuyori lifted the confinement. That is why people can weep at his stone today — they can, because we know what was in his mind.
Oyamada never gave a reason. There is only the act, with no words attached to it. Four and a half centuries on, nobody knows what was inside him.
Mihata Tatenashi was, above all, an instrument for stating your reason in front of witnesses. He never used it. Had he stood in council and said I cannot abandon the people of Gunnai, he would have been treated like Kiso and Anayama. Disliked, perhaps. Not stained.
And it still has not been said. The memorial society can only say he did not betray. Instead of giving the reason, it denies the act.
It looks to me like the same failure, being made a second time, four hundred and fifty years later.
What my daughter said
People say history is written by the winners.
Something else is happening in Yamanashi. The losing side preserved its own oath after its own defeat and has gone on positioning people by it ever since — and it was the winner who carried the device out of the house and made it national.
People still travel to Tano. The memorial society trying to overturn a four-hundred-and-fifty-year-old verdict and the visitors walking to the place where Katsuyori died are two faces of one machine. Where the sanction survives, the mourning survives. You don’t get one without the other.
I went to the festival because of that BBC documentary. In it, a man four and a half centuries later showed the camera a war fan said to have been given to his family by Shingen himself, kept as an heirloom. The correspondence between object and household has not been broken.
That is why a descendant can step forward at the festival. He has the proof in his hands.
When I got home I told my daughter about it — that one of the generals had been played by his own descendant.
She said:
How sad. He can never leave that, can he.
I had watched the same moment and seen pride. She heard restraint. I don’t think either of us was wrong. From the outside, honor and constraint are indistinguishable — and I suspect they are not clearly distinguishable from the inside either.
So I no longer think Mihata Tatenashi was a device for punishing. It was a device for holding people in place. To swear before a witness was to promise not to move from your position afterward.
Katsuyori, leaning the banner against a pine at Tano, was one of the people who could not leave his. He can never leave that, can he — my daughter’s line describes that day exactly.
And yet, standing in that festival, there were also people with no house at all. The town mayors and company executives playing the twenty-four generals. The man handed a traitor’s banner with no connection to the name on it. The young foreigners working so hard at their Japanese lines.
Tomorrow they all go home. The role had a way in and a way out.
So if you go, learn the one line.
Mihata Tatenashi mo go-shōran are.
Say it with the crowd. For about three seconds you will be helping to reconstitute the witness — agreeing, together, that the Banner and the armor are watching, which is the only thing that ever made either of them work. Then you can put it down and walk out, which is more than some people there can do.
The objects are intact in their shrine and their temple. It was never the objects.
The Mihata is at Unpō-ji and the Tatenashi armor at Kanda Tenjin Shrine, both in Kōshū City, Yamanashi. Keitoku-in, at the site of Katsuyori’s death, is near Kai-Yamato Station. The Shingen-ko Festival is held in Kōfu each April.