The Battle of Sekigahara — What Happened and How It Ended
The Battle of Sekigahara was the decisive clash on October 21, 1600, between the Eastern Army of Tokugawa Ieyasu and the Western coalition led by Ishida Mitsunari, which determined the future ruler of Japan. The fighting lasted only a few hours: the turning point came when the commander Kobayakawa Hideaki switched to Ieyasu's side. Ieyasu won, and in 1603 became shogun, founding a state that lasted until 1868.
The name refers only to the place — a quiet village at a crossroads in Mino Province — but in truth, the fate of the entire country was decided in this valley. Formally, two coalitions of daimyo fought, but the outcome depended on a few commanders who had decided before the battle whose side they were really on. Below is how the day of October 21, 1600, unfolded and what it changed for the next two and a half centuries.
What Happened: The Battle of Sekigahara
On October 21, 1600 (the 15th day of the 9th month of the 5th year of Keichō by the old calendar), two coalitions of daimyo met near the village of Sekigahara in Mino Province, in a narrow valley at a crossroads of important roads. The Eastern Army was led by Tokugawa Ieyasu, the Western Army formally by Mōri Terumoto but in reality by Ishida Mitsunari. The battle began in the morning in thick fog after a night of rain and went on for nearly six hours without a clear advantage, until the commander Kobayakawa Hideaki switched to Ieyasu's side and struck his former allies. After that, the Western Army collapsed within hours.
- 1598: Toyotomi Hideyoshi dies, leaving power to a council of five regents for the five-year-old heir Hideyori — among the regents, Tokugawa Ieyasu is first among equals.
- 1599–1600: Ieyasu violates the agreements on collective rule; two rival coalitions of daimyo form around him and Ishida Mitsunari.
- October 21, 1600, early morning: the armies finish forming up at Sekigahara between 6 and 7 o'clock — the rain has stopped, but the fog remains thick.
- The first to attack is Ii Naomasa's unit — it strikes Ukita Hideie's position, bypassing the established order of precedence.
- Kobayakawa Hideaki descends from Mount Matsuo and attacks the camp of his former ally Ōtani Yoshitsugu — other western units follow suit.
- Shimazu Yoshihiro with the remnants of his unit breaks through the enemy lines instead of retreating by the usual route.
Why It Came to This
The formal cause was the death of Hideyoshi in 1598. He left power to his five-year-old heir Hideyori and divided governance between two councils: five regents (go-tairō) headed by Ieyasu and five administrators (go-bugyō), among whom was Mitsunari. But already in 1599–1600, Ieyasu began arranging marriage alliances in violation of the general ban, without consulting the other regents — and Mitsunari led those dissatisfied with this accumulation of power. Thus the country split into two camps before the first shot was fired.
Who Took Part
| Side | Commander | Outcome |
|---|---|---|
| Eastern Army | Tokugawa Ieyasu | Victory; in 1603, the title of shogun |
| Western Army | formally Mōri Terumoto, in fact Ishida Mitsunari | Crushed within hours; Mitsunari captured and executed in Kyoto |
| Shimazu clan (Western Army) | Shimazu Yoshihiro | Broke through the enemy lines; only a handful of men survived, but the clan kept its domains |
Name and Kanji: 関ヶ原の戦い
The name 関ヶ原の戦い is read せきがはらのたたかい (Sekigahara no Tatakai) and breaks down into parts: 関 means 'barrier', 原 means 'plain, field', 戦い means 'battle, fight', and the small ヶ between them is an old connective particle, a contraction of 箇. Literally — 'the battle on the plain by the barrier': the place got its name in ancient times, long before 1600.
戦 — значение: war, battle, to fight — онъёми: セン — кунъёми: いくさ、たたか.う、おのの.く、そよ.ぐ、わなな.く — 13 штрих(ов). 戦 — 'war, battle, fight': 13 strokes. The same character appears in 戦い (tatakai, 'battle', hence the name of the event) and in the word 挑戦 (chōsen, 'challenge, attempt').
| Japanese | Reading | Translation |
|---|---|---|
| 関ヶ原の戦い | Sekigahara no Tatakai · Sekigahara no Tatakai | The full Japanese name of the battle |
| 関ヶ原 | Sekigahara · Sekigahara | The site of the battle — a village and district in Mino Province |
| 東軍 | tōgun · tōgun | The Eastern Army — the side of Tokugawa Ieyasu |
| 西軍 | seigun · seigun | The Western Army — the side of Ishida Mitsunari |
| 武将 | bushō · bushō | Military commander, general |
| 裏切り | uragiri · uragiri | Betrayal — what decided the outcome of the battle |
What the Japanese Call It
Besides 関ヶ原の戦い, the event is called 関ヶ原合戦 (Sekigahara Kassen) — the same word 'battle', but in an older variant. There is also a third name — 天下分け目の戦い, 'the battle that divided the realm': this is how people refer to the moment that determined the future ruler of the whole country. The toponym itself is much older than 1600: since the 7th century, the Fuwa barrier stood at this crossroads, one of the three ancient barriers of Japan.
Listen and repeat the name of the battle and military terms of the era.
In Anime, Games, and Film
- Sengoku Basara: Samurai Heroes — several missions are dedicated to Sekigahara ('Sekigahara: Betrayal', 'Zero Hour', 'Assembly', and others) — the final battle for most characters in the game.
- Sengoku Basara: End of Judgement (anime, 2014) — the series is built around the preparations for Sekigahara and the battle itself, including duels between commanders.
- Samurai Warriors (Sengoku Musou) — Sekigahara is one of the central and most frequently replayed missions of the series, with different outcomes depending on the player's choices.
- Nobunaga's Ambition: Sphere of Influence — a separate historical scenario of 1600, where you can play a campaign for any of the participating sides.
- Total War: Shogun 2 — a historical battle available as a separate mission for Ishida Mitsunari against Tokugawa Ieyasu.
- Sekigahara (2017) — a Japanese film by Masato Harada with Junichi Okada as Mitsunari, based on the novel by Ryōtarō Shiba and the first attempt to show the battle on screen in full.
What Was Distorted for the Sake of the Plot
Games, and Sengoku Basara in particular, reduce Sekigahara to a series of spectacular one-on-one duels between commanders — in reality, formations of several thousand men fought, not duelists. A common genre technique is clear weather for the sake of battlefield readability, although sources agree on thick fog after a night of rain. The 2017 film, on the contrary, tried to be accurate and became the first attempt to show the battle on screen in full, rather than in an abridged retelling.
FAQ
- What is the Battle of Sekigahara?
- The Battle of Sekigahara (関ヶ原の戦い) was the decisive clash on October 21, 1600, between the Eastern Army of Tokugawa Ieyasu and the Western coalition of Ishida Mitsunari. Ieyasu's victory opened the way to the title of shogun in 1603 and determined the structure of the Japanese state for two and a half centuries.
- When did the Battle of Sekigahara take place?
- The battle took place on October 21, 1600 — by the old lunar calendar, the 15th day of the 9th month of the 5th year of the Keichō era. The fighting at the village of Sekigahara in Mino Province lasted only a few hours: it began in the morning fog and ended with the rout of the Western Army while it was still light.
- Who took part in the Battle of Sekigahara?
- Coalitions of daimyo fought on both sides — by various estimates, from 160,000 to 200,000 people including reserves. The Eastern Army was led by Tokugawa Ieyasu, the Western Army formally by Mōri Terumoto but in fact by Ishida Mitsunari; among the western commanders were Ukita Hideie and Shimazu Yoshihiro.
- How did the Battle of Sekigahara end?
- The Western Army collapsed within hours when Kobayakawa Hideaki switched to Ieyasu's side. Mitsunari was captured and executed in Kyoto, the lands of the losers were redistributed, and in 1603 Ieyasu became shogun. From this battle came the distinction between fudai daimyo (who served him before it) and tozama daimyo (who pledged allegiance after).
- What is the Battle of Sekigahara called in Japanese?
- 関ヶ原の戦い, read せきがはらのたたかい (Sekigahara no Tatakai) — 'the battle of Sekigahara'. There is an older variant of the same name — 関ヶ原合戦 (Sekigahara Kassen), and the event is also called 天下分け目の戦い, 'the battle that divided the realm': this is how people refer to the battle that determined the future ruler of the whole country.
- How is the Battle of Sekigahara shown in games and anime?
- Sekigahara has dedicated levels in Sengoku Basara and Samurai Warriors, a historical scenario in Nobunaga's Ambition, and a historical battle in Total War: Shogun 2. The anime Sengoku Basara: End of Judgement is built entirely around this battle, and the film Sekigahara (2017) showed it on screen in full for the first time.
Sources
Updated: 2026-09-11