The battle of Sekigahara, which occurred in 1600, is one of the biggest events in Japanese history. The highlight of the battle has been said to be the betrayal of Hideaki Kobayakawa. However, historians are trying to re-create the Sekigahara story by reviewing the few remaining primary sources and some of the secondary ones which were reliable.
Location and History
Introduction
The battle of Sekigahara, which occurred on the 15th of September 1600 (according to the lunar calendar), is one of the biggest events in Japanese history. The highlight of the battle has been said to be the betrayal of Hideaki Kobayakawa. The widely accepted theory says the followings. Hideaki first supported the western allies and settled on Matsuoyama Castle, in the south of the Sekigahara field. However, he still waited to see the battle for a while, wondering which ally would be better, the eastern or the western. He had made a secret agreement with Ieyasu Tokugawa, who was the top of the eastern allies, to support. Initially, Koyakawa did not move, therefore Ieyasu got tired of waiting. He then ordered his soldiers to shoot at the Hideaki’s troops. The shooting was called “Toi-deppo” which means to force by guns. Hideaki was very surprised to hear that. In that instance, he quickly decided to support the eastern allies. This indecision by Kobayakawa lead to the death of Mitsunari, but gave victory to Ieyasu.
Recent studies suggest the betrayal of Hideaki and the Toi-deppo story. The whole story of the Sekigahara battle is consisted of very few primary sources and many other secondary sources. The Toi-deppo story comes from one of the secondary sources. The Sekigahara Battle is long. One part of the story refers to Toi-Deppo, which was first written in the Keicho Gunki, a war chronicle which was written over 50 years after the battle. If the story is a fiction, the timing of Hideaki’s decision would also be doubtful. Historians are trying to re-create the Sekigahara story by reviewing the few remaining primary sources and some of the secondary ones which were reliable. In addition, Matsuoyama Castle has been said to be the base of Hideaki Kobayakawa during the Sekigahara battle. However, it would also be important to know when and how the castle was built and used.
This article will explain three different theories of Hideaki and Matsuoyama Castle with three different viewpoints. The viewpoints will include: a. What and where did Hideaki go before the Sekigahara battle? b. Why did Sekigahara become the battlefield and when and how did Hideaki settle on Matsuoyama Castle? c. When did Hideaki really decided to support the eastern allies?
The theories on this article will include:
The defacto theory including the Toi-deppo story
The theory that Hideaki was not a betrayer
The theory that the western allies would attack Matsuoyama Castle
As a preface, I will describe the prehistory of Hideaki and Matsuoyama Castle before the battle.
Hideaki and Matsuoyama Castle before Sekigahara Battle.
Hideaki was born in 1582 as the fifth boy of Iesada Kinoshita who was the big brother of Kitano-mandokoro, the first lady of Hideyoshi Toyotomi. He was adopted by Hideyoshi when he was a child and was raised by Kitano-mandokoro. Surprisingly, Hiedaki celebrated his Coming of Age at only 7 years old and became a noble. This was because he was one of the candidates to be Hideyoshi’s successor. However, after Hideyori Toyotomi, Hideyoshi’s own child was born, Hideaki was adopted again by the Kobayakawa Clan. Hideyoshi thought Hideyori would have become his successor.
There is an interesting episode about that from a war chronicle as follow. Hideyoshi originally wanted to adopt Hideaki to the Mori Clan and for the Mori Clan to take over, which was the head family of the Kobayakawa Clan. Takakage Kobayakawa, the lord of the clan offered to Hideyoshi to accept Hideaki to protect his master. However, according to historians, Takakage probably decided it by himself. This was because Takakage was an independent lord after he was given his own territory by Hideyoshi. Takakage assumed he would return the territory to Hideyoshi so that he could build a good relationship with him.
Hideaki’s new territory was at Chikuzen Province (which is part of Fukuoka Prefecture now) which was one of the basements for the invasion of Korea by Hideyoshi. Hideaki also went to Korea as the supreme commander when he was 16 years old (so, it was just a formality). However, when he went back to Japan in 1598, he was forced to move to Echizen Province (the current Fukui Pref.) by Hideyoshi. The reason for it is uncertain. War cornicles suggest that Hideaki made a mistake in the invasion, while historians speculate that Hideyoshi wanted to rule Chikuzen Province directly to boost his invasion. The fact is, after Hideyoshi died, that Hideaki returned to Chikuzen Province and was considered one of the great lords of Japan, following the members of Counsil of Five Elders in the top government. This would trigger the Battle of Sekigahara.
Matsuoyama Castle was located on the border between Omi (the current Shiga Pref.) and Mino (Gifu Pref.) Provinces. A record says that a retainer of Nagamasa Azai, who owned Omi Province, was assigned to the castle during the Sengoku Period. This was probably because Nagamasa was against Nobunaga Oda who owned Mino Province at that time. Nobunaga would eventually get Omi Province before the castle was abandoned. On the 10th of Argust, 1600 (according to the luna calendar), Mitsunari Ishida entered Ogaki Castle. Mitsunari ordered his retainer to resume Matsuoyama Castle. Mitsunari thought that his Western Allies would attack the Eastern Allies based on Ogaki Castle, backed up by other mountain castles. Matsuoyama Castle was one of them. A historian speculates that Mitsunari thought that Terumoto Mori, the greatest lord in the Western Allies would enter Matsuoyama Castle. Anyway, the castle was refortified again to prepare for the battle.
Defacto theory including Toi-deppo story
It is confirmed that the Western Allies captured Fushimi Castle on the 1st of August (according to the lunar calendar). It is also certain that the troops of Hideaki Kobayakawa joined the attackers as the main force. After that, according to the de facto theory, many of the Western Allies, including Mitsunari Ishida, stayed in Ogaki Castle, while Hideaki marched over to Omi Province (the current Shiga Province). There is evidence of his actions there. remains at a temple of the province. There is a noticeboard where Hideak’s soldiers were asked not to be violent in the temple. Hideaki still supported the Western Allies, however, he also negotiated with the Eastern Allies. A secret letter from Nagamasa Kuroda and Yoshinaga Asano was given to Hideaki before the battle. The letter is written as followed.
“We (Nagamasa and Yoshinaga) will need to serve Kitano-mandokoro. You need to decide whether or not you will support us until Ieyasu arrives here.”
Kitano-mandokoro took care of Nagamasa earlier on. He managed to persuade Hideaki that it would be needed to support the Eastern Allies if Hideaki wanted to serve Kitano-mandokoro from then on.
Ieyasu arrived at Aakasaka Camp on the 14th of September, near Ogaki Castle. He wanted to have an open field battle, which he was good at, so he needed to lure Mitsunari out from the castle. Ieyasu intentionally announced that he would attack Sawayama Castle, which was Mitsunari’s home and far to the west from Ogaki. When Mitsunari heard this, he was surprised and left the castle in a hurry, got ahead of Ieyasu, and took up positions on Sekigahara Field on the way to Sawayama. Hideaki also reached Matsuoyama Castle in the south of Sekigahara in accordance with Mitsunari’s instructions. Historians speculate that Mitsunari might have tried to escape to Sawayama Castle with his own decision. This is because a letter of Hiroie Kikkawa, who was one of the members of the Western Allies on Nangusan Castle between Ogaki and Sekigahara, says so. However, Mitsunari couldn’t do that because had to prevent the eastern allies from invading Sekigahara on the way there. Yoshitsugu Otani, a lord of the Western Allies only expected that Hideaki would betray him, therefore, Yoshitsugu’s troops moved closer to Matsuoyama.
The battle between the Eastern and the Western Allies occurred early in the morning on the 15th of September. It went back and forth until noon. Hiroie’s troops on Nangusan and Kobayakawa’s troops didn’t move because of their secret pact with Ieyasu. However, Ieyasu got annoyed as Hideaki had also promised that he would join the Eastern Allies. That’s why Ieyasu ordered the Toi-deppo (a way to induce or encourage solider to move by shooting directly at them). Hideaki’s decision happened around noon. Some of the soldiers who joined the Western Allies testified after the battle as followed:
“The Eastern Allies and Otani’s troops battled each other 6 or 7 times in the morning. Kobayakawa’s troops, then, rushed down from the mountain into Otani’s side and destroyed them.”
As for the Toi-deppo story, it may be a fiction as mentioned above. However, a historian found another tradition that might have been the origin of the story as followed:
An old man in Bizen Province (the current Okayama Pref.) heard about an interesting story from Kobayakawa’s retainer. During the battle, Hideaki heard gunshots at the foot of the mountain. His retainers reported that the shooters of the Eastern Allies said that the gunshots were not intentional and that they just misfired. The retainers also added it might have included something else.
The historian speculates that the shooting could have been an indirect warning from Ieyasu. However, this theory is still not the number one theory according to historians.
Theory that Hideaki was not a Betrayer
I will next explain a new theory about Hideaki and Matsuoyama Castle. Accorting to this theory, it is uncertain where Hideaki was after the battle of Fushimi Castle just before the Sekigahara Battle. The de facto theory says he was in Omi Province at that time. However, that comes from the family records of the Inaba Clan which was written during the Edo Period. The records also say their founder, who was a senior vassal of Hideaki, captured Matsuoyama Castle for the Eastern Allies. That means the records were manipulated by his descendants to show their contributions to the current shogunate, which may not be plausible now. On the other hand, a lord of the Eastern Allies reported that Hideaki stayed in Ogaki Castle just before the Sekigahara Battle. This is contradictory. Overall, in my opinion, I think Hideaki was undecided as to who he would support until the moment he rode up the mountain.
In fact, there is also no certain evidence where Hideaki was positioned at the beginning of Sekigahara Battle. However, another evidence suggests it. The letter of Hiroie Kikkawa, mentioned above, says an interesting matter just before the battle.
“The Western Allies moved from Ogaki Castle to Yamanaka (the west of Sekigahara) in order to rescue Yoshitsugu Otani because Hedeaki would be fighting against them.”
According to the letter, Hideaki and Yoshitsugu had already arrived early to inspect the field. In addition, a letter that Masamune Date wrote, who was reported from his relative about the Sekigahara battle, also says:
“The Western Allies moved from Ogaki Castle to support Nangusan Castle.”
Overall, historians speculate why Sekigahara became the battlefield as followed: Ieyasu at Akasaka Camp first tried to attack Nangusan Castle. Mitsunari heard about this and tried to intercept Hideaki, so he decided to leave Ogaki Castle and went to Sekigahara. Then, Hiroie Kikkawa at Nangusan Castle surrendered to Ieyasu who next ordered his troops to chase after Mitsunari. The Western Allies eventually reached Yamanaka and positioned themselves, which was not Sekigahara. This is another different point from the defacto theory.
If they are true, Hideaki declared he would join the Eastern Allies at the latest the day before the battle. The battle started around 10am, where Hideaki joined it at the same time, and the Western Allies were defeated by the Eastern Allies quickly. They are different from the defacto story. The theories of the starting time of the battle are also different depending on the testimonies of the participants. Historians speculate as followed. In the early morning at Sekigahara field which was covered in fog. The Otani troops went ahead from the Yamanaka area to the Sekigahara field. It first battled against the frontline of the Eastern Allies. When the fog cleared up around 10am, the Kobayakawa troops attacked the Otani troops which would eventually be destroyed. After that, the main forces from both the Eastern and Western Allies fought against each other at the Yamanaka area, but the Western Allies were also destroyed in a short amount of time. Ieyasu wrote in his letters that Hideaki worked well in Sekigahara and his troops destroyed the Western Allies including Mitsunari in Yamanaka.
The theory that Western Allies would attack Matsuoyama Castle
The previous theory can help us understand that Hideaki was not a betrayer in the middle of the battle. However, the theory is consisted of much circumstantial evidence. It doesn’t show us the clear conflicted formation between Hideaki and the Western Allies. (Situations of battles may sometimes be like that.) Another theory by another historian may clear this up. The main idea of the theory is that the Sekigahara Battle happened when the Western Allies tried to destroy Hideaki’s troops on Matsuoyama Castle. In this theory, Hideaki was stationed in Omi Province and negotiated with the Eastern Allies before entering the castile, the same as the defacto theory. However, the theory speculates that Hideaki made his decision to join the Eastern Allies in advance of reaching Matsuoyama Castle, which is the different point from the defacto theory.
The biggest difference in this theory from other ones is the reason why Mitsunari left Ogaki Castle. According to this theory, Mitsunari heard about Hideaki’s rebellion during the meeting at the castle on the 14th of September, the day before the Sekigahara Battle. Mitsunari decided to leave the castle to destroy Hideaki. One of the pieces of evidence for the theory is the same part of the letter Hiroie Kikkawa wrote, as the previous theory uses. It says “the Western Allies went from Ogaki Castle to Yamanaka (near Sekigahara) in order to rescue Yoshitsugu Otani because Hideaki would be fighting against them” in the previous theory. However, the same part says in this theory that “The Western Allies were going to attack Yamanaka, which meant Hideaki’s rebellion became obvious, so Yoshitsugu Otani followed them from Ogaki Castle.” Why are the interpretations of the same part so different between each other? This is probably because letters of warlords were usually written using simple and often vague facts, so that the interpretations of the current historians may sometimes become different. Another reason is sometimes the messenger would be intercepted, and vague instructions would be hard for the enemy to understand.
Mitsunari was positioned on Jigai-ga-oka Hill in front of Matsuoyama Castle on Matsuoyama Mountain, not on Sasaoyama Mountain which the defacto theory says. According to the testimonies of some soldiers who joined the battle, the Ukita and Konishi’s troops were on the frontline against the castle to the south, back upped by the Shimazu’s troops. Mitsunari’s troops were in the eastern side of the Shimazu. The Eastern Allies including Ieyasu chased after Mitsunari in order to rescue Hideaki who had already joined them. That’s why they saw, from the east, the Western Allies like Miatunari on the frontline, back upped by the Shimazu’s troops, which were written in other records. The Otani’s troops finally arrived and was positioned at Sekigahara field in the eastern side of his allies. As a result, they were first attacked by the Eastern Allies, then sandwiched between the Eastern Allies and Hideaki’s troops, and eventually destroyed.
Some of the soldiers who joined the Western Allies testified after the battle as followed:
“The Eastern Allies and Otani’s troops battled each other 6 or 7 times in the morning. Kobayakawa’s troops, then, rushed down from the mountain into Otani’s side and destroyed them.”
This is the same testimony that proves the defacto theory. It is very interesting that this testimony proves two different situations.
If you are at JR Sakura Station, the place, where the castle ruins are located, it may looks simple at first. However, if you go there by walking up on the slopes, you will be surprised to see the spacious area on the top. Visitors coming from other places may feel the same way, too.
Features
Introduction
If you are at JR Sakura Station, the place, where the castle ruins are located, it may look simple at first. However, if you go there by walking up on the slopes, you will be surprised to see the spacious area on the top. Visitors coming from other places may feel the same way, too.
From Main Gate to Main Enclosure
Let us go from the ruins of the main gate to the center of the castle. Unfortunately, only a part of the earthen walls remains today.
There were some large enclosures inside the gate, such as Higashi-so-kuruwa. They were turned into schools, parking lots, and a square. There is also Sakura Castle Park control center in front of the square, which shows some exhibitions of the castle. The square had the main hall for the lord and another one for the retirement residence of Masayoshi Hotta at the end of the Edo Period.
You will eventually reach the center of the castle, which has been turned into Sakura Castle Park. You will first see the remaining large dry moat. It looks beautiful, covered in grass, however, it must have been deeper and more fortified in the past.
You will next reach the ruins of the third gate, which was the first gate towards the center. The third enclosure is inside of the gate, and it was the residential area for the senior vassals in the past. You will find a mini crater in the enclosure. This is the trace of another dry moat, which has been filled. If you go further, you will see the statues of Townsend Harris and Masayoshi Hotta who tried to open Japan to the rest of the world.
Then, you will reach the ruins of the second gate, the entrance of the second enclosure. The enclosure had had the first main hall for the lord before the one outside the third enclosure was built. There were also the rice warehouses in the back of the enclosure. You can still see its stone foundations there, too.
You will eventually reach the main enclosure after going across the dry moat of the enclosure. there are the ruins of the first gate.
Climbing down from Main Enclosure
The main enclosure is all surrounded by earthen walls, so you may feel like you are being wrapped up. This area is the western edge of the plateau. There was the other main hall inside, however, it was rarely used just for ceremonies. This was because it was considered exclusive for the shoguns.
You can walk on the earthen walls around the enclosure. If you walk from the first gate ruins on the earthen walls, you will pass by the ruins of Do-yagura (the copper turret). The turret had a mysterious tradition. It says that the turret was originally built by Dokan Ota, the founder of Edo Castle, called “Shoyoken”, and moved from the castle. However, we cannot confirm whether or not the turret was moved from Edo Castle. However, if it had remained, it would have become a National Treasure of Japan.
If you go further, you will eventually reach the earthen base of the main tower. The tower was directly built on the base and its outside walls leaned on the earthen walls of the enclosure. That was why people saw the tower three-leveled from the outside but four-leveled from the inside. The tower was used as the warehouse for weapons. It was unfortunately burned down after a thief robbed it of guns and left his lantern there.
There are the other ruins of the corner turret in the enclosure. The turret also has the tradition which says it originally came from Motosakura Castle. That may have been the reason why it deteriorated sooner than the others and was renovated during the Edo Period.
Let us next get out of the enclosure through the ruins of the back gate and climb down the slopes of the plateau. The slopes are steep which made the castle fortified. You will eventually see some trails on the mid slopes, which are the belt enclosures of the castle. The enclosures were said to have originally been dry moats and were changed to the trails by being filled naturally. If you look up the main enclosure, you will realize it is protected by the natural terrain even though it doesn’t have stone walls.
You will eventually arrive at the foot of the plateau and see the southern barbican enclosure. If you go around the enclosure, you will see it is still surrounded by water moats. It looks very defensive and cool! If you enter the enclosure as well, you will see the outside which you walked around on.
I recommend you to go back to the belt enclosure and walk on it to the other western barbican enclosure. The enclosure still has its earthen walls and water moats in good conditions. There is the only remaining building at its entrance, called Yakui-mon gate. However, No one knows for certain its original name and position, because it was moved multiple times from the current position that it is in now.
Looking at Umadashi system and Dry Moats
If you don’t mind, it may be better to walk around the plateau to another entrance from the north to the castle. It was called Tamachi-mon which was the back gate of the castle, on Atago slope. It is now the front gate of the National Museum of Japanese History. A large enclosure of the castle, called Shinoki-kuruwa has become the museum. The enclosure was originally used as Samurai residences and was turned into barracks for the Japanese Imperial Army before the museum. It has been used effectively because it is massive.
The floor space of the museum is about 35,000 square meters big. It exhibits the Japanese histories by classifying 5 different periods. If you want to look through all of them, you may have to spend all day long. It may be better to split up your visits to fully see everything.
Going back to the attractions of the castle, the Umadashi system has been restored near the museum. The system was a fortified square position in front of Shinoki Gate, which was surrounded by dry moats. The long side of the square is 121m long and the short side is 40m long, same as the original. The dry moats were originally 5.6m in depth but is only 3m in depth probably for safety reasons. The system is only connected by a narrow path to the gate. It was once filled by the Japanese Imperial Army before its restoration.
The Shinoki Gate Ruins have no buildings now, and its inside is the third enclosure. So, you can visit the second and main enclosures again. However, let us go to another place by walking down from the plateau again. It is a pond, called Uba-ga-ike, which means “The Pond of a Nursing Mother”. The name comes from a sad and unfortunate story. It says that one day, a nursing mother took the daughter of a senior vassal to the pond. However, she didn’t keep her eyes on the daughter, which lead to the daughter drowning in the pond She felt very sad and guilty about it, so, she decided to throw herself into the pond as well. For the castle, this pond divided the main gate and the back gate sides to force the defenders protect the castle quickly. It also became famous for Japanese iris and croaking sounds of frogs during the peaceful Edo Period.
You can go back from the pond to the main gate ruins by passing through a path which was another dry moat. The path has a fork which still looks like the dry moat. If you go straight, you will eventually reach the entrance of the park near the gate ruins.
Visiting Samurai Residences and Sakura Juntendo Memorial Building
Atter visiting the castle ruins, let us go to Sakura Samurai Residences. The residence area is in Miyakoji of Sakura City, which originally had middle-class warriors’ residences. However, the current area exhibits three different residences: one of the remaining one for middle class warriors, another one form high-class warriors and finally, the other one form low-class warriors. The last two residential areas were moved from other areas, making it accessible to the public for viewing.
These residences were owned and maintained by the Sakura Domain like official residences. They were made differently by each warrior’s class. That was because of the class system as well as the budgetary restrictions of the domain. For example, the entrance of the high-class residence looks high in quality, but the others are simpler. The walls of the high class’s one used white plasters, while the others only used brown mud walls. The high and middle class’s ones used fine Tatami mats in their rooms, however the low class can only use simple mats without the edge decorations.
You should also try to walk along Hiyodori-zaka Slope near the residences, which was the commuting route to the castle. The route goes down on a trail, surrounded by bamboo trees, which looks exactly same as it used to.
We will finally go to Sakura Juntendo Memorial Building. It was originally built by Taizen Sato as his Rangaku (Dutch studies) school and clinic. Part of it opens to the public as a museum. The museum is about 2km away from the main gate ruins of the castle and was at the edge of the castle town. This is probably because Taizen was not an official doctor of the domain. A guide of the museum suggested to me another speculation. Taizen’s father was an agent in lawsuits who was against the policies of Tadakuni Mizuno, the top of the government. Therefore, Taizen might have had difficulties in his work in Edo City. He might also have been accommodated by Masayoshi Hotta. If it’s true, Sakura Juntendo was also like a place of refuge.
One of the exhibitions of the museum is the miniature model of the original buildings. You can see the buildings were so large. It is said that over one thousand students were there in total.
Another interesting exhibition is the original medical board which is hung on the top of the wall. The clinic mainly offered surgeries. However, the doctors didn’t use anesthesia because it was still dangerous at that time. Therefore, patients endured the pain because they wanted to get well after that.
The clinic is the origin of Juntendo University in Tokyo, one of Taizen’s successors who founded it. However, there is still the current Sakura Juntendo Clinic next to the museum. The spirits of Sakura are alive.
My Impression
Honestly, at first, I thought the castle park looked like a natural park. However, the more I looked around, the more my impressions changed. Currently it’s trendy for cities to revive castles across Japan. I think Sakura City does not need to ride the boom. This is because the city has already preserved the land of the castle as the park. The city can take enough time and be patient when developing it further. The important thing is preserving it as accurate as possible. In addition, you can still enjoy the castle ruins even without its visible buildings. So I highly recmmend you visit Sakura Catle in the future!