Battle of Sekigahara: Encyclopedia - Battle of Sekigahara

Battle of Sekigahara

The Battle of Sekigahara or popularly known as the Realm Divide was a decisive battle on September 15, 1600 (on the ancient Chinese calendar, October 21 on the modern calendar) that cleared the path to the Shogunate for Tokugawa Ieyasu. Though it would take three more years for Tokugawa to consolidate his position of power over the Toyotomi clan and the daimyo, Sekigahara is widely considered to be the unofficial beginning of the Tokugawa bakufu, the last shogunate to control Japan.

At what is now Sekigahara, Gifu Prefecture, Tokugawa Ieyasu's forces battled those led by Ishida Mitsunari, who was loyal to Toyotomi Hideyoshi's son and designated heir, Hideyori. The tide of the battle turned when Kobayakawa Hideaki on Ishida's side betrayed his allies during the fight. Although at first Kobayakawa merely stood on the sidelines of the battle, not taking part in the battle, Tokugawa eventually ordered his arquebusiers to fire at Kobayakawa's troops, after which Kobayakawa began fighting on Tokugawa's side. It was in fact this betrayal that led to Tokugawa's decisive victory and the end of the fighting amongst the council of five regents.

Battle of Sekigahara - Background and pretext

Even though Toyotomi Hideyoshi unified Japan and consolidated his power, his ill-fated invasion of Korea significantly weakened the Toyotomi clan's power as well as the loyalists that continued to serve and support the Toyotomi clan after Hideyoshi's death. The war also worsened the continuous conflict between the army commanders and the bureaucrats under Hideyoshi. The presence of Hideyoshi and his brother, Hidenaga kept the two sides from anything more than quarrelling, but when both of them died, the conflicts exacerbated and developed into open hostilities. Later on, Maeda Toshiie's death all but removed any trace or pretense of friendliness between the two factions.

Most notably, Kato Kiyomasa and Fukushima Masanori were publicly critical of the bureaucrats, especially Ishida Mitsunari and Konishi Yukinaga. Tokugawa Ieyasu took advantage of this situation, and recruited them, redirecting the animosity to weaken the Toyotomi clan.

Battle of Sekigahara - Beginning

The death of Maeda Toshiie meant that there was no one to rival Tokugawa Ieyasu anymore, in terms of seniority, rank, and overall influence within the Toyotomi clan. Thus, many were worried that Tokugawa would take over Toyotomi's legacy just as Toyotomi had with Oda Nobunaga's. This worry was especially evident amongst the loyalist bureaucrats, who suspected Tokugawa of agitating unrest amongst Toyotomi's former vassals.

Later, a supposed conspiracy to assassinate Tokugawa Ieyasu surfaced, and many Toyotomi loyalists, including Maeda Toshiie's son, Toshinaga, were accused of taking part and forced to submit to Ieyasu's authority.

However, Uesugi Kagekatsu, one of Hideyoshi's appointed regents, defied Ieyasu by building up his military. When Tokugawa officially condemned him and demanded that he come to Kyoto to explain himself before the emperor, Uesugi's chief advisor, Naoe Kanetsugu responded with a counter-condemnation that mocked Tokugawa's abuses and violations of Toyotomi's rules, in such a way that Tokugawa was infuriated.

Thus, Tokugawa summoned the help of various supporters and led forces northward to attack Uesugi, who was accused by Tokugawa of treason against the Toyotomi clan, but Ishida Mitsunari, grasping the opportunity, rose up in response and created an alliance to challenge the Tokugawa supporters. Ishida, collaborating with Otani Yoshitsugu and Ankokuji Ekei, seized the various daimyo's hostages in Osaka Castle and raised an army to fight Tokugawa. This western alliance was officially headed by Mori Terumoto, although Mori distanced himself from most of the fight.

Tokugawa then left some forces to keep Uesugi in check and marched west to confront the western forces. A few daimyo, most notably Sanada Masayuki, left Tokugawa's alliance, although most, either bearing grudges against Ishida or being loyal to Tokugawa, stayed with him.

The Toyotomi clan did not take part in this battle, nor did it officially condone any side.

Battle of Sekigahara - List of Commanders

Battle of Sekigahara - Eastern Army Tokugawa Force

• Tokugawa Ieyasu
• Maeda Toshinaga
• Date Masamune
• Kato Kiyomasa
• Fukushima Masanori
• Hosokawa Tadaoki
• Asano Yukinaga
• Ikeda Terumasa
• Kuroda Nagamasa
• Kato Yoshiakira
• Tanaka Yoshimasa
• Todo Takatora
• Mogami Yoshimitsu
• Yamauchi Katsutoyo
• Hachisuka Yoshishige
• Honda Tadakatsu
• Terasawa Hirotaka
• Ikoma Kazumasa
• Ii Naomasa
• Matsudaira Tadayoshi
• Oda Nagamasu
• Tsutsui Sadatsugu
• Kanamori Nagachika
• Tomita Nobutaka
• Furuta Shigekatsu
• Wakebe Mitsuyoshi
• Horio Tadauji
• Nakamura Kazutada
• Arima Toyouji

Battle of Sekigahara - Western Army Ishida Force

• Mori Terumoto (official head of the alliance)
• Uesugi Kagekatsu
• Ukita Hideie
• Shimazu Yoshihiro
• Kobayakawa Hideaki (defected)
• Ishida Mitsunari (de facto head of the alliance)
• Konishi Yukinaga
• Mashita Nagamori
• Ogawa Suketada (defected)
• Otani Yoshitsugu
• Wakisaka Yasuharu (defected)
• Ankokuji Ekei
• Satake Yoshinobu
• Oda Hidenobu
• Chosokabe Morichika
• Kutsuki Mototsuna (defected)
• Akaza Naoyasu (defected)
• Kikkawa Hiroie (defected)
• Natsuka Masaie
• Mori Hidemoto
• Toda Katsushige
• Sanada Masayuki

Battle of Sekigahara - The Battle

Ishida, in his home Sawayama Castle, met with Outani Yoshitsugu, Mashita Nagamori, and Ankokuji Ekei. Here, they forged the alliance, and invited Mori Terumoto to be its head.

Ishida then officially declared war on Tokugawa and lay siege to the Fushimi Castle, garrisoned by Tokugawa retainer Torii Mototada on July 19. Afterwards, the western forces captured various Tokugawa bases in the Kansai region. Within a month, the western forces had moved into the Mino province, where Sekigahara was located.

Back in Edo, Tokugawa received news of the situation in Kansai and decided to deploy his forces. He had some former Toyotomi daimyo engage with the western forces while he split his troops and marched west toward the Osaka Castle. Tokugawa Ieyasu's main forces marched on Tokaido whilst his son, Hidetada, led another group through Nakasendo. However, Hidetada's forces were bogged down as he attempted to besiege Sanada Masayuki's Ueda Castle. Even though the Tokugawa forces numbered some 38,000, an overwhelming advantage over Sanada's mere 2,000, they were still unable to capture the strategist's well-defended position. As a result, Hidetada's forces never arrived on the battlefield at Sekigahara.

Knowing that Tokugawa was heading toward Osaka, Ishida decided to abandon his positions and marched to Sekigahara. On September 15, the two sides started to deploy their forces. The eastern forces had 74,000 men, whilst the western forces numbered around 82,000.

Even though the western forces had tremendous tactical advantages, Tokugawa had already contacted many daimyo on Ishida's side, promising them land and leniency after the battle should they switch sides. This led some western commanders holding key positions to hesitate when pressed to send in reinforcements or join the battle that was already in progress.

Mori Hidemoto and Kobayakawa Hideaki were two such daimyo. They were in such positions that if they decided to close in on Tokugawa forces, the western forces would in fact have Tokugawa surrounded on three sides. Mori Hidemoto, shaken by Tokugawa's promises, also persuaded Kikkawa Hiroie not to take part in the battle.

Even though Kobayakawa had responded to Tokugawa's call, he remained hesitant and neutral. As the battle grew more intense, Tokugawa Ieyasu finally ordered arquebusiers to fire at Kobayakawa's direction, a move that forced Kobayakawa to join the battle on Tokugawa's side.

His forces assaulted Outani Yoshitsugu's position, which quickly fell apart as Outani was already engaging Todo Takatora's forces. Seeing this act of treachery, western generals such as Wakisaka Yasuharu, Ogawa Suketada, Akaza Naoyasu, and Tsuki Mototsuna immediately switched sides, turning the tide of battle.

The western forces disintegrated afterwards, and the commanders scattered and fled. Some committed suicide (such as Outani), some were captured (e.g. Ishida, Konishi, and Ankokuji), and others were able to return to their home provinces (e.g. Shimazu Yoshihiro and Mori Terumoto).

Battle of Sekigahara - Aftermath

Tokugawa Ieyasu redistributed the lands and fiefs of the participants, generally rewarding those who assisted him and displacing, punishing, or exiling those who fought against him. In doing so, Tokugawa gained control of many former Toyotomi territories. Ishida Mitsunori, Konishi Yukinaga, and Ankokuji Ekei were publicly executed. The influence and reputation of the Toyotomi clan and its remaining loyalists drastically decreased, although from the Toyotomi clan's point of view, the battle was technically only an internal conflict between Toyotomi vassals; however, in fact, Tokugawa Ieyasu was later made Seii Taishōgun, a position that had been left vacant since the fall of the Ashikaga shogunate. This change in official ranks also reversed the subordinate position of the Tokugawa clan. In any case, Tokugawa did not gain any casus belli to take action against the frail Toyotomi clan; rather, it would take more political manoeuvres for Tokugawa to destroy Toyotomi once and for all.

See also the Siege of Osaka.

Even though the battle demonstrated Tokugawa's authority, many clans, especially those on the western side, became bitter about their displacement or what they saw as a dishonorable defeat or punishment. For example, the Mori clan, which was displaced from its home provinces to Chōshū-han, remained angry toward the Tokugawa shogunate, because the clan never actually took part in the battle.

The Shimazu clan blamed the defeat on its poor intelligence-gathering. Whilst they were not displaced from their home province, Satsuma, they did not become completely loyal to the Tokugawa shogunate either. Taking advantage of its distance from the capital as well as its improved espionage, Satsuma-han, near the end of the Tokugawa shogunate, demonstrated that it was virtually an autonomous kingdom independent from the Tokugawa shogunate.

Tosa's ruling clan, the Chosokabe clan, was stripped of its title and domain and sent into exile. Former Chosokabe retainers never quite came to terms with the new ruling family, the Yamauchi clan. In fact, the Yamauchi clan made a distinction between its own retainers and former Chosokabe retainers, giving them lesser status as well as discriminating treatment. This class distinction continued even generations after the fall of the Chosokabe clan.

The three of these disgruntled groups would in two centuries collaborate to bring down the Tokugawa shogunate.

Battle of Sekigahara - Trivia

• According to tradition, Miyamoto Musashi, the legendary kensei, was present at the battle among the ranks of Toyotomi Hideyori's army. Supposedly, he fought well and escaped the defeat of Hideyori's forces unharmed. Whether this is fact or myth is unknown; Musashi would have been around 16 years of age at the time.

Categories: 1600 | Battles of Japan | Edo period

Adapted from the Wikipedia article "Battle of Sekigahara", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki