The battle of Sekigahara in 1600 was one of the most important moments of Japanese history during the Sengoku Jidai. After decades of growing as a junior ally to Nobunaga Oda, and then the same to Hideyoshi, Ieyasu Tokugawa was now primed to take control of Japan for himself now that the former head of the Toyotomi had passed away and left his five year old son to rule. In his way was Mitsunari Ishida and the Western Army, a collection of Daimyo who opposed Ieyasu's grab at power and claimed he sought to overthrow the Toyotomi. They were right, of course, and the battle was clearly over who would rule Japan.
Ieyasu won the battle and became Shogun, leading to a series of events wherein the Tokugawa would remove Hideyori and fully take control of Japan for over two centuries.
So let's explore this battle, or rather this campaign, numerous sieges and battles having been waged during this conflict despite the short period.
How could things have changed from OTL? Let's start off with maybe wondering if the Tokugawa could have had a more decisive vict-No, no, that's sort of impossible. Maybe Torii Mototada survives long enough that Mitsunari is dealt with, maybe Hidetada never attempts his siege of Ueda, and maybe Naomasa Il is not injured when chasing down the Shimazu and wipes their forces out. Either way, it's hard to improve the Tokugawa's position. They won pretty handily, despite it being close at points, and without too many important figures dying.
So with that, we need to turn to the Western Army. Led by Mitsunari Ishida, we can already see the first mistake. Mitsunari rose to the top because of his skills as an administrator and in the tea ceremony, which was a big thing in Oda and then Toyotomi circles, and stayed there due to Hideyoshi's favour. He had skills, this was true, but not in military matters or in inter-personal relations. He could be an accomplished diplomat, convincing his friend Yoshitsugu Otani (who was off to join the Tokugawa) to join him and swayed Hideaki Kobayakawa by offering to make him Kampaku until Hideyori was of age.
That said, he wasn't great at it when it most counted. Otherwise loyal Toyotomi retainers such as Kiyomasa Kato and Masanori Fukushima joined Ieyasu because Fuck Mitsunari, and his plot to assassinate Ieyasu failed so badly that the latter chose to save him from harm because he was the ideal opponent. There were flashes of skill, such as choosing to fight in Sekigahara after Sakon's raid in the Tokugawa, and in his strategy throughout, but he was an alienating character who engineered his own destruction in the battle.
Despite the farces, bickering, and betrayals that defined this coalition, the Western Army did have a strong chance of victory, and there are some scenarios to explore to see how this could have been.
POD #1: The Shimazu Night-Raid at Ogaki
After the raid on the Tokugawa in what would be known as the Battle of Kuisegawa IOTL, there was deliberation on how to deal with the Tokugawa. Mitsunari knew that Ogaki wasn't Ieyasu's only option and that he could easily bypass Ogaki Castle (the base of the Western Army) and head for Osaka where Hideyori was or Mitsunari's home castle of Sawayama. In deliberations, one suggestion was offered by Yoshihiro Shimazu. Ieyasu's forces had only just arrived with his Tokaido forces (his son Hidetada handling the Nakasendo) after a two-week long march in their armour. The forces were tired, hungry, and generally open to a surprise night-raid. Ukita Hideie, Mitsunari's second in command, supported the plan.
The highly-overrated Sakon Shima, however, saw the plan as cowardly and used his momentum from Kuisegawa to convince Ukita to reject the Shimazu plan. This led to Mitsunari choosing to fight in Sekigahara, and the Shimazu feeling insulted enough to refuse to advance when ordered and only attacked when they felt like it.
The plan could have easily worked. Yoshihiro's logic was solid, the army was tired, and I imagine the Eastern Army thought that the time for ambushes had ended with Sakon's efforts. At best, Ieyasu may have been slain and the war won. What's more likely is that the army is savaged and either retreat or hold their position to consider their next move. Ieyasu thought that time was of the essence when it came to taking Osaka and Sawayama, which was what drove him into Sekigahara IOTL, and there is a key element that may drive him there as well.
Hidetada was meant to arrive with the Nakasendo forces, numbering around 38,000, to beef up the Tokugawa forces whilst the Date and others dealt with the Uesugi in the East. Instead, he's dealing with Ueda and may possibly arrive at a roughly similar time to OTL, meaning right after the battle. If Mitsunari gets the flash of brilliance he did IOTL, and Ieyasu arrives at roughly the same time, the battle might have been different had certain generals been slain ITTL.
Of course the numbers game isn't everything. Maybe Ieyasu waits a while longer and meets with Hidetada, replacing the lost soldiers and raising morale. Hideaki may take longer to betray the cause, but both he and the Mori still have factors playing against Mitsunari that the Shimazu raid isn't going to solve. Unless it ends the man himself, the raid may only just give the Western Army a second meaningful victory.
POD #2: Terumoto Mori leads the Western Army
Terumoto Mori gets a raw deal. Seen as a lesser man to his grandfather and father, he often gets painted as indecisive, and easily fooled. When it comes to your Samurai Warriors and Sengoku Basara, the man even gets replaced by his grandfather Motonari Mori (who died in 1571), and is barely a foot-note when it comes to their depictions of the Sengoku Jidai, let alone the Sekigahara Campaign.
This is anything but the truth.
One of Hideyoshi's chosen advisers for Hideyori alongside Toshiie Maeda, Ieyasu, Kagekatsu Ueusgi, and Ukita Hideie, Terumoto was one of the reasons why the Western Army was a viable force. Without him, the Western Army would have lacked a large portion of the men and wealth needed to be a viable opponent to Ieyasu. It was for that reason that Yoshitsugu had convinced Mitsunari to grant Terumoto the rank of Commander In Chief of the Western Army, despite Mitsunari's ego demanding that he be the one in charge.
Terumoto, however, was then forced to remain in Osaka Castle whilst his cousin Hidemoto (another unfairly maligned general) represented the Mori in battle as Mitsunari's price. This angered many Mori retainers including Kikkawa Hiroie who wrote letters to Eastern Army generals such as Kuroda Nagamasa and Il Naomasa offering to keep the Mori from entering battle in exchange for leniency for the Mori when Ieyasu won. This was not carried out by Ieyasu, who likely never intended to due to Terumoto's powerful position, but Kikkawa still managed to prevent the Mori from entering battle by preventing a charge down from the mountain where they had waited. Ieyasu thus avoided being boxed in as per Mitsunari's plan.
Let's say then that Terumoto decides that if he's the Commander in Chief, then he's the damn Commander in Chief and what he says goes. Mitsunari is instead told to wait at Osaka whilst Terumoto handles military affairs. There'd be a likely stand-off, but the former will likely bend if Terumoto threatens neutrality or worse. Terumoto was a skilled commander who knew when to delegate. We'd see the Shimazu night-raid be executed, and then have Mount Nagyu be held by a different commander instead of Hidemoto Mori, maybe Sakon Shima, Ukita Hideie, or Yoshitsugu Otani?
Another thing to consider is the Osaka hostages, but that depends on whether Gracia Hosokawa (Mitsuhide Akechi's daughter) actually committed suicide or if her death was ordered by her husband Tadaoki to ensure that she couldn't be used as a hostage/served as a martyr to weaken Mitsunari with. Terumoto may use a lighter touch than Mitsunari, but the results may be the same in terms of fallout leading to the escape of many other generals' wives.
Without Kikkawa's betrayal, we'd likely see the Tokugawa become flanked from the front and behind. Hideaki Kobayakawa had been unsure on whether to betray the Western Army, so it could be that the potential loss of the Tokugawa drives him to actually join in with the Western Army and charge in from his flank. The Tokugawa are smashed and Ieyasu is killed or captured, Kobayakawa serves as Kampaku (he was Terumoto's cousin by adoption), and it all seems fine, right?
Well, there is the question of who rules. Mori or Toyotomi? Not to mention Mitsunari's potentially bruised ego playing a role in court games. Hideaki's death may signal TTL's version of the Siege of Osaka in terms of wrapping things up.
POD #3: Terumoto Mori joins the Eastern Army
Yes, yes, I know what I said about the Tokugawa having a broadly decent campaign, but bear with me.
Terumoto Mori was conflicted IOTL on who to join. He was leaning towards Ieyasu, and both Kikkawa Hiroie and Hidemoto Mori supported this option as the likely winner, and had to think about preserving his lands worth 1.2 million koku (1 being the amount of rice needed to feed one person for a year) during the conflict. It was the advice of Ekei Ankokuji that swayed him to the Western Army, just as he did with Hideyoshi's peace offer in 1582. We all know how that went, and Terumoto lost his home province of Aki and ended up with only 360,000 koku worth of land only due to Kikkwa Hiroie's protestations to Ieyasu.
The POD here is obvious, Terumoto joins the Eastern Army instead of the Western Army, despite Ekei and Yoshitsugu's offer of Commander in Chief. This immediately creates an issue for Mitsunari and Ieyasu. For Mitsunari, his whole plan relied on Ieyasu being lured east by the Uesugi and then smashed by the Western Army while he was busy there. Only now it seems that he's the one who is being flanked on two sides now. If he declares war, he has to fight the Mori and Eastern Army, but if he doesn't then Ieyasu is just going to crush the Uesugi and leave him without allies.
For Ieyasu, he now has a viable rival to deal with, even if the Uesugi and Mitsunari are wiped out. Both men had wealthy provinces, an old saying was that Ieyasu could create a road of rice from Kanto to Kyoto, while Terumoto could make a road of gold and silver from his lands to Kyoto. The campaign ITTL will be much easier, Mitsunari may try and move out, reasoning that the Uesugi will keep Ieyasu busy, but then he gets promptly destroyed facing the Mori and Ieyasu.
The problem for the Tokugawa now lies in how the West is controlled by the Mori, who will be holding Osaka, which will make it harder for Ieyasu to assume the rank of Shogun while the Mori are around to note the defiance of Hideyori's authority. Both Ieyasu and Terumoto IOTL lived long enough to see OTL's Siege of Osaka, and a conflict would be inevitable, so TTL's version of the Siege of Osaka may be a wider-scale campaign in terms of conquest. I'd put money on the Tokugawa, but not without a few more bloody noses than OTL, especially now that Toyotomi loyalists who hated Mitsunari have an easier banner to fight under.
So there are the PODs for Sekigahara. You could argue that 'Kikkawa Hiroie not preventing the Mori from attacking' is one, but I think the impact is broadly similar to Terumoto being the de facto as well as de jure leader, in that the Mori and Mitsunari would eventually come to blows.
Any thoughts or comments?
Ieyasu won the battle and became Shogun, leading to a series of events wherein the Tokugawa would remove Hideyori and fully take control of Japan for over two centuries.
So let's explore this battle, or rather this campaign, numerous sieges and battles having been waged during this conflict despite the short period.
How could things have changed from OTL? Let's start off with maybe wondering if the Tokugawa could have had a more decisive vict-No, no, that's sort of impossible. Maybe Torii Mototada survives long enough that Mitsunari is dealt with, maybe Hidetada never attempts his siege of Ueda, and maybe Naomasa Il is not injured when chasing down the Shimazu and wipes their forces out. Either way, it's hard to improve the Tokugawa's position. They won pretty handily, despite it being close at points, and without too many important figures dying.
So with that, we need to turn to the Western Army. Led by Mitsunari Ishida, we can already see the first mistake. Mitsunari rose to the top because of his skills as an administrator and in the tea ceremony, which was a big thing in Oda and then Toyotomi circles, and stayed there due to Hideyoshi's favour. He had skills, this was true, but not in military matters or in inter-personal relations. He could be an accomplished diplomat, convincing his friend Yoshitsugu Otani (who was off to join the Tokugawa) to join him and swayed Hideaki Kobayakawa by offering to make him Kampaku until Hideyori was of age.
That said, he wasn't great at it when it most counted. Otherwise loyal Toyotomi retainers such as Kiyomasa Kato and Masanori Fukushima joined Ieyasu because Fuck Mitsunari, and his plot to assassinate Ieyasu failed so badly that the latter chose to save him from harm because he was the ideal opponent. There were flashes of skill, such as choosing to fight in Sekigahara after Sakon's raid in the Tokugawa, and in his strategy throughout, but he was an alienating character who engineered his own destruction in the battle.
Despite the farces, bickering, and betrayals that defined this coalition, the Western Army did have a strong chance of victory, and there are some scenarios to explore to see how this could have been.
POD #1: The Shimazu Night-Raid at Ogaki
After the raid on the Tokugawa in what would be known as the Battle of Kuisegawa IOTL, there was deliberation on how to deal with the Tokugawa. Mitsunari knew that Ogaki wasn't Ieyasu's only option and that he could easily bypass Ogaki Castle (the base of the Western Army) and head for Osaka where Hideyori was or Mitsunari's home castle of Sawayama. In deliberations, one suggestion was offered by Yoshihiro Shimazu. Ieyasu's forces had only just arrived with his Tokaido forces (his son Hidetada handling the Nakasendo) after a two-week long march in their armour. The forces were tired, hungry, and generally open to a surprise night-raid. Ukita Hideie, Mitsunari's second in command, supported the plan.
The highly-overrated Sakon Shima, however, saw the plan as cowardly and used his momentum from Kuisegawa to convince Ukita to reject the Shimazu plan. This led to Mitsunari choosing to fight in Sekigahara, and the Shimazu feeling insulted enough to refuse to advance when ordered and only attacked when they felt like it.
The plan could have easily worked. Yoshihiro's logic was solid, the army was tired, and I imagine the Eastern Army thought that the time for ambushes had ended with Sakon's efforts. At best, Ieyasu may have been slain and the war won. What's more likely is that the army is savaged and either retreat or hold their position to consider their next move. Ieyasu thought that time was of the essence when it came to taking Osaka and Sawayama, which was what drove him into Sekigahara IOTL, and there is a key element that may drive him there as well.
Hidetada was meant to arrive with the Nakasendo forces, numbering around 38,000, to beef up the Tokugawa forces whilst the Date and others dealt with the Uesugi in the East. Instead, he's dealing with Ueda and may possibly arrive at a roughly similar time to OTL, meaning right after the battle. If Mitsunari gets the flash of brilliance he did IOTL, and Ieyasu arrives at roughly the same time, the battle might have been different had certain generals been slain ITTL.
Of course the numbers game isn't everything. Maybe Ieyasu waits a while longer and meets with Hidetada, replacing the lost soldiers and raising morale. Hideaki may take longer to betray the cause, but both he and the Mori still have factors playing against Mitsunari that the Shimazu raid isn't going to solve. Unless it ends the man himself, the raid may only just give the Western Army a second meaningful victory.
POD #2: Terumoto Mori leads the Western Army
Terumoto Mori gets a raw deal. Seen as a lesser man to his grandfather and father, he often gets painted as indecisive, and easily fooled. When it comes to your Samurai Warriors and Sengoku Basara, the man even gets replaced by his grandfather Motonari Mori (who died in 1571), and is barely a foot-note when it comes to their depictions of the Sengoku Jidai, let alone the Sekigahara Campaign.
This is anything but the truth.
One of Hideyoshi's chosen advisers for Hideyori alongside Toshiie Maeda, Ieyasu, Kagekatsu Ueusgi, and Ukita Hideie, Terumoto was one of the reasons why the Western Army was a viable force. Without him, the Western Army would have lacked a large portion of the men and wealth needed to be a viable opponent to Ieyasu. It was for that reason that Yoshitsugu had convinced Mitsunari to grant Terumoto the rank of Commander In Chief of the Western Army, despite Mitsunari's ego demanding that he be the one in charge.
Terumoto, however, was then forced to remain in Osaka Castle whilst his cousin Hidemoto (another unfairly maligned general) represented the Mori in battle as Mitsunari's price. This angered many Mori retainers including Kikkawa Hiroie who wrote letters to Eastern Army generals such as Kuroda Nagamasa and Il Naomasa offering to keep the Mori from entering battle in exchange for leniency for the Mori when Ieyasu won. This was not carried out by Ieyasu, who likely never intended to due to Terumoto's powerful position, but Kikkawa still managed to prevent the Mori from entering battle by preventing a charge down from the mountain where they had waited. Ieyasu thus avoided being boxed in as per Mitsunari's plan.
Let's say then that Terumoto decides that if he's the Commander in Chief, then he's the damn Commander in Chief and what he says goes. Mitsunari is instead told to wait at Osaka whilst Terumoto handles military affairs. There'd be a likely stand-off, but the former will likely bend if Terumoto threatens neutrality or worse. Terumoto was a skilled commander who knew when to delegate. We'd see the Shimazu night-raid be executed, and then have Mount Nagyu be held by a different commander instead of Hidemoto Mori, maybe Sakon Shima, Ukita Hideie, or Yoshitsugu Otani?
Another thing to consider is the Osaka hostages, but that depends on whether Gracia Hosokawa (Mitsuhide Akechi's daughter) actually committed suicide or if her death was ordered by her husband Tadaoki to ensure that she couldn't be used as a hostage/served as a martyr to weaken Mitsunari with. Terumoto may use a lighter touch than Mitsunari, but the results may be the same in terms of fallout leading to the escape of many other generals' wives.
Without Kikkawa's betrayal, we'd likely see the Tokugawa become flanked from the front and behind. Hideaki Kobayakawa had been unsure on whether to betray the Western Army, so it could be that the potential loss of the Tokugawa drives him to actually join in with the Western Army and charge in from his flank. The Tokugawa are smashed and Ieyasu is killed or captured, Kobayakawa serves as Kampaku (he was Terumoto's cousin by adoption), and it all seems fine, right?
Well, there is the question of who rules. Mori or Toyotomi? Not to mention Mitsunari's potentially bruised ego playing a role in court games. Hideaki's death may signal TTL's version of the Siege of Osaka in terms of wrapping things up.
POD #3: Terumoto Mori joins the Eastern Army
Yes, yes, I know what I said about the Tokugawa having a broadly decent campaign, but bear with me.
Terumoto Mori was conflicted IOTL on who to join. He was leaning towards Ieyasu, and both Kikkawa Hiroie and Hidemoto Mori supported this option as the likely winner, and had to think about preserving his lands worth 1.2 million koku (1 being the amount of rice needed to feed one person for a year) during the conflict. It was the advice of Ekei Ankokuji that swayed him to the Western Army, just as he did with Hideyoshi's peace offer in 1582. We all know how that went, and Terumoto lost his home province of Aki and ended up with only 360,000 koku worth of land only due to Kikkwa Hiroie's protestations to Ieyasu.
The POD here is obvious, Terumoto joins the Eastern Army instead of the Western Army, despite Ekei and Yoshitsugu's offer of Commander in Chief. This immediately creates an issue for Mitsunari and Ieyasu. For Mitsunari, his whole plan relied on Ieyasu being lured east by the Uesugi and then smashed by the Western Army while he was busy there. Only now it seems that he's the one who is being flanked on two sides now. If he declares war, he has to fight the Mori and Eastern Army, but if he doesn't then Ieyasu is just going to crush the Uesugi and leave him without allies.
For Ieyasu, he now has a viable rival to deal with, even if the Uesugi and Mitsunari are wiped out. Both men had wealthy provinces, an old saying was that Ieyasu could create a road of rice from Kanto to Kyoto, while Terumoto could make a road of gold and silver from his lands to Kyoto. The campaign ITTL will be much easier, Mitsunari may try and move out, reasoning that the Uesugi will keep Ieyasu busy, but then he gets promptly destroyed facing the Mori and Ieyasu.
The problem for the Tokugawa now lies in how the West is controlled by the Mori, who will be holding Osaka, which will make it harder for Ieyasu to assume the rank of Shogun while the Mori are around to note the defiance of Hideyori's authority. Both Ieyasu and Terumoto IOTL lived long enough to see OTL's Siege of Osaka, and a conflict would be inevitable, so TTL's version of the Siege of Osaka may be a wider-scale campaign in terms of conquest. I'd put money on the Tokugawa, but not without a few more bloody noses than OTL, especially now that Toyotomi loyalists who hated Mitsunari have an easier banner to fight under.
So there are the PODs for Sekigahara. You could argue that 'Kikkawa Hiroie not preventing the Mori from attacking' is one, but I think the impact is broadly similar to Terumoto being the de facto as well as de jure leader, in that the Mori and Mitsunari would eventually come to blows.
Any thoughts or comments?
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