This is going to be a post about a favourite topic of mine: The Battle of Sekigahara.

関ヶ原合戦図屏風 (Battle of Sekigahara folding screen)

Battle of Sekigahara folding screen (Image via Wikipedia)

For those who don’t know, The Battle of Sekigahara (I’ll refer to it simply as Sekigahara after this point) was a turning point in Japanese history. Up until Sekigahara, Japan had been divided amongst several Daimyo (local, all powerful lords) and, despite the best intentions of certain people (Nobunanga Oda and Hideyoshi Toyotomi, to name but two of them) it remained that way for a LONG time.

The seeds that lead up to Sekigahara were sewn back in the Genpei Wars of the 10th century. Basically, it was a war between the Taira and Minimoto clans of Japan. These were two of the most prolific clans of Samurai that Japan had ever seen (up until this point). I’m not going to go into a lot of detail here about the Genpei Wars, that’s for better historians than I, but I’ll leave a couple of links to more information at the end of this section.

Wikipedia entry on The Genpei Wars [LINK]

Wikipedia entry on the Heike Monogatari [LINK]

English language version of the Heiki Monogatari LINK]

 The Build-up to Sekigahara

OK. So, in the mid 16th century (about 1560) Nobunanga Oda was trying to unify Japan under one rule. After an unsuccessful invasion by the “Mongols” (Made up of Mogol generals, a Chinese army and captured Korean troops) it was decided that Japan should fortify it’s defences against outsiders, so massive armies were conscripted, training was given and weapons were dolled out. It turned out that none of this was needed, as the Mongols never bothered trying to invade Japan again.

Side Note: Not after their failed attempts and the intervention of the Kamikaze (or sacred wind)

 Wikipedia article of the attempted Mongol invasion of Japan and what I mean by the Kamikaze [LINK]

Side note: A prolific warrior during the Genpei wars (and main character of the Genji video games) Yoshitsune Minamoto had disappeared after the Genpei wars had ended. It is rumoured by some that he left Japan, and became Kublai Kahn. Kublai Kahn was the leader of the invasion force. It’s far more likely that he returned to his roots (had gone back home to the North) and became a Buddhist Monk, though.

So with a massive army of conscripts, no way to pay them, and no major wars for them to fight in, it was decided that they would be disbanded. This created a massive amount of unemployment for trained soldiers. These unemployed soldiers had a choice:

  1.  Go back to what they did before they were conscripted
  2. Become bandits

Guess which option most of them chose?

Nobunanga Oda (along with a whole bunch of other people) decided that they needed to unite the country. Their idea was that if they could unite the country under one Shogun, then the people would be happier and it would be a peaceful land.

Nobunanga nearly accomplished this, but was all but executed by his own right-hand man, Akechi Mitsuhide at the Honno-ji Temple. When he was killed, Toyotomi Hideyoshi took over Nobunanga’s plan to unify Japan.

A few years after Toyotomi did this, he decided that the next big step would be to conquer China. The only problem with this, is that he would have to go through Korea. He sent envoys and messengers to the Korean capital telling them of his plan. The main thrust of his letters and messages was, basically, thus:

 If you join my forces in conquering China, I’ll make sure that no-one in Korea is harmed.

Worried that Chinese and Japanese forces would end up fighting in Korea, the Korean King decided to turn down Toyotomi’s offer, hoping that he would re-think his plan and not attack China. Toyotomi, however had other ideas.

He sent his forces into Korea anyway. The plan was to march through Korea, up to the border and into China. Along the way, his forces took Pusan and Seoul. Historical records differ in opinion, but it is thought that fleeing Korean’s destroyed parts of royal buildings in Seoul and Pusan rather than let these buildings fall into the hands of the invading Japanese. Records of the time state that the opposite had happened: that the Japanese destroyed the buildings out of spite.

The battles and long marches took their toll on the Japanese forces. With no knowledge of the internal layout of the country, they relied on the few food stores that had not been destroyed by the fleeing Korean refugees. With supply routes not yet established, the Japanese forces found that they were running out of food, quickly. Not to mention the ferocity with which the Korean people fought back; which caused a large amount of deaths and casualties on the Japanese side.

By the time they’d reached the Chinese border, the Chinese had amassed an army that, basically chased them out of Korea. The Japanese ended up leaving around 30,000 of their own troops in Korea either dead or to die.

The retreat was covered up from Toyotomi (who never left Japan during the planned invasion) as all the messages sent back were hand written, and he was illiterate (having grown up on a farm and fought his way into Nobunanga’s good books). Also, when Chinese envoys came to Japan to discuss the retreat of Japanese forces, all communication had to be carried out in written Chinese; which made it even easier for Toyotomi’s court to cover up the retreat.

The truth eventually came out, though, and Toyotomi was, understandably, livid. This wasn’t until a few years after the planned invasion failed, though.

By 1598, Toyotomi died of, what is now suspected to be, untreated diabetes. He had decided, before he died, to elect a council of regents to look after the courtly affairs until his son and heir was old enough to take control of the country.

 Side note: It’s this period of time that the novel (and TV series) Shogun by James Clavell is set

 One year later, Toshie Maeda died. He was one of the more powerful regents, and his death left a rift in the council that was never fixed.

On one side of the rift, there was:

  •  Tokugawa Ieyasu – the most powerful member of the council of regents (even before Toshie died)
  • Damian Kuroda – a recently converted Christian
  • Katō Katsushima

On the other side of the rift, there was:

  • Ishida Mistunari
  • Augustin Konishi – another recently converted Christian

Damian Kuroda, Katō Katsushima and Augustin Konishi had all served during the Korean/Chinese invasion, and had all been generals during it. Konishi and Kuroda had been the first two generals to make it into Pusan, and decided not to let Katsushima in to Pusan. Katsushima had had no choice but to ride on to Seoul (which is much further to the North than Pusan). When the order came to retreat, Konishi and Kurada had left Katsusima to die.

Ishida had served longer as a Samurai, and was respected more because of it. However, he’d only served in supply and logistics as a career soldier. This meant that, compared to the other Samurai, he was seen as experienced in military life, but not matters pertaining to war. This meant that, for conflict matters, Tokugawa was preferred over Ishida.

After the attempted invasion of Korea/China, the failures were blamed (rightly or wrongly) on the growing Christian population. As it was the Christian generals who had retreated first, and left their compatriots to die. Shortly before he died, Hideyoshi began forcing certain leaders to denounce their Christian religious beliefs. Ishida was able to gain ground with the Christian lords who would not denounce their faith; but Tokugawa had already gained all of the lords who had denounced theirs (guess which side had more troops?)

Also around this time, Ieyasu impounded the cargo of a shipwrecked trading vessel called the Liefde. He claimed the cargo his own (19 cannon, 500 muskets, 5000 cannon balls and 300 chain shot). This gained him even more support with the local lords.

Sekigahara – October 21st 1600

The night before the battle, neither side slept. This was because of a storm that kept all of the soldiers awake. The generals and high ranking Samurai in their tents couldn’t sleep for the sound of the rain pattering against the roofs of said tents. Whereas the lower ranking Samurai and the foot troops (Ashigaru) were forced to spend the night outside.

Most of the countryside around Sekigahara was recently harvested. This was, after all, rice land. This meant that most of the battle ground was covered with rice paddies which were filling up with water. This meant that the fighting would take place in a sodden, quagmire not fit to stand in let alone fight in.

By the morning, the rainfall had turned to fog. According to witnesses, the fog was that thick that the troops couldn’t see more than a few feet ahead of themselves. This meant that the first shots that were fired, were fired when one group of Samurai (literally) bumped into another group from the opposing side. Both commanders withdrew their men, quickly, fearing that they had stumbled into a trap.

Tokugawa’s forces attacked first. Naomasa, the leader of the “Red Devils” (named so because all of their armour was dyed red, and Nomasa had horns sticking out of his helmet), charged his entire cavalry unit. This was against direct orders from Tokugawa (Wait and see what the enemy does). When asked about it, after the battle Nomasa’s excuse was that he wanted to check on the disposition of the enemy’s focus.

Kuroda and Hosokawa troops charged directly for Ishida himself. Their justification was that if they could take him out early, then the battle could end quickly.

 Side Note: This seems to be standard practise with large group of Samurai. They always seemed to want to be in the middle of the action as soon as possible

 Calf deep in muddy rice paddies, Christian Samurai (on Ishida’s side) and former Christians (on Tokugawa’s side) were soon fighting each other in a bloody struggle. Troops who had recently fought side by side were now being killed by the sword and bullets of their friends. Not only that but many were trampled to death or drowned in the muddy paddies.

Ishida began to fire his 5 cannon on the battlefield, causing a great effect to the moral of his troops but very little damage to any of the opposing troops. He also sent his reserves charging at Tokugawa’s flank, but these were taken out by Tokugawa’s reserves in quick stead.

Shimazu and Kobayakawa forces made up the “wings” of Ishida’s Crane battle formation and should have flanked the main Tokugawa forces that were being fired on by the cannon as soon as the cannon started firing. But both forces refused to charge. Kobayakawa’s excuse was that, when the order came to charge, the messenger never alighted his horse. This was seen as a grave insult.

Konishi became enraged with the Kobayakawa forces and quickly sent a messenger to their position, demanding that they join the fray. Ōtani Yoshitsugu, Konishi’s fellow commander (who was a crippled, half-blind leper who had to be carried onto the battlefield in a Palanquin) felt that, since the Kobayakawa weren’t being attacked, they had already sided with the Tokugawa forces.

Kobayakawa had, in fact, accepted deals from both sides yet marched to Skigahara with Ishida’s forces. But when Tokugawa ordered his men to begin taking pot-shots at the Kobayakawa forces, the Kobayakawa turned on the Ishida forces.

Kobayakawa’s forces charged on Ōtani. But Ōtani had seen through Kobayakawa’s plan and prepared his forces. When Kobayakawa attacked Ōtani’s flank, Ōtani’s troops were ready for it and held them off, quite admirably.

Most of Kobayakawa’s men fell where they stood. But the charge on Ōtani’s troops had a massive negative affect on Ishida’s moral. Now that Tokugawa could see that Ishida’s Crane “only had the one wing,” Tokugawa charged on both Ōtani and Ishida. Kobayakwa’s remaining troops “hacked their way to Ōtani” and Ōtani committed seppuku, right there on the battlefield.

Konishi’s men, seeing the death of Ōtani and his entire army, routed. But Konishi refused to run, he was channelling the, so called, “Spirit of the Samurai.” Instead, he threw himself into the fray, fighting tooth and nail until injuries (“wounded from head to foot”) forced him to yield and be taken prisoner.

The Shimazu had waited far too long, and found themselves surrounded by Tokugawa forces. In an attempt to run, Shimazu Yshihiro ordered his men to “punch a hole” in the Tokugawa forces that he might retreat. This meant volunteering most of his troops to a suicide mission that would allow him to successfully retreat.

By 2pm, Tokugawa, who had watched the battle from his commanding stool clad in hi armour, called fro his head gear. He was going to take the battlefield personally. Before he left for the battlefield, he muttered:

 “At the moment of victory, tighten the straps of your helmet”


Tokugawa called for all 87 lords who opposed him (that had not fallen in the battle) to commit suppuku. Only Konishi refused, saying that suicide was a mortal sin. Konishi was lead to his death, flanked by non-believers Ishida Mistunari and the Buddhist warrior monk Ankokui Ekei. He was denied the last rights (specifically be Damien Kuroda); prayed with rosaries; and bowed to an image of the Virgin Mary before his head was hacked off. It took three blows with the sword before it came loose from his shoulders.

Konishi’s first son was executed; his adopted Korean daughter, Julia, spent the rest of her life in exhile; his second son disappeared from all records – it is rumoured that he lived out his live as a Buddhist monk; and his daughter, Maria was disowned by her husband (Dario So) and fled to the Christian safe haven of Nagasaki.

The Tokugawa went on to be the longest serving family of Shogun, and Ieyasu finally achieved the goal of Nobunanga Oda and Toyotomi Hideyoshi: Unifying Japan and bringing about 250 years of peace. Peace that was only broken when the American’s wanted to use Nagasaki as an Eastern port. But that’s a story for another time.

Until then, Stay safe and have fun,


Jamie is a .NET developer specialising in ASP.NET MVC websites and services, with a background in WinForms and Games Development. When not programming using .NET, he is either learning about .NET Core (and usually building something cross platform with it), speaking Japanese to anyone who'll listen, learning about languages, writing for this blog, or writing for a blog about Retro Gaming (which he runs with his brother)