On July 22, 672, Prince Ōama’s forces reached the Seta River.
On the western side of the river were Prince Ōtomo and the ministers of the Ōmi court.
The Nihon Shoki records that the troops were lined up so densely that the rear was out of sight, banners covered the fields, and the sound of gongs and drums echoed.
While this description emphasizes the size of the army, it also conveys how the Ōmi court had gathered its remaining forces near the capital.
Crossing the Seta River would bring them close to the Ōmi Ōtsu Palace.
The vanguard of the Ōmi army guarding the bridge was Chison.
A trap using planks was set up on the bridge, and arrows greeted Prince Ōama’s forces as they attempted to cross. The advance was halted on the narrow bridge.
At that moment, Ōita no Kimi Wakaomi stepped forward.
He discarded his long spear, donned additional armor, drew his sword, and rushed onto the bridge.
The Nihon Shoki recounts that he crossed the planks under a hail of arrows, cut the ropes connected to the trap, and entered the enemy’s position.
The Ōmi forces began to crumble.
Chison tried to cut down retreating allies to push them back, but he couldn’t stop the tide and was himself killed near the bridge.
Prince Ōtomo left Seta.
The next day, on the 23rd, with nowhere left to flee, the prince hanged himself at “Yamamae.”
This was the Battle of Seta Bridge, marking the end of the Jinshin War.
In the riverbed about 80 meters south of the current Seta Karahashi, remnants of bridge piers believed to date from the mid-7th century have been confirmed.
Prince Ōama had departed from Yoshino on June 24.
Less than a month passed until the fierce battle at Seta Bridge.
During that short period, intense fighting continued in various areas such as Yamato, Iga, and Ōmi.
July 2: Forces Move from Fuwa
By June 27, Prince Ōama had entered Mino and established his base around Nogami.
Murakuni no Muraji Oyori and others, who had gone ahead, gathered 3,000 men in Mino and secured the Fuwa route.
Troops from Iga and Ise also joined, and messengers were dispatched to conscript soldiers from the provinces along the Tōkaidō and Tōsandō routes.
On July 2, Prince Ōama sent his forces out in two directions.
The Yamato front was entrusted to Ki no Omi Ahema, O no Omi Honji, Miwa no Kimi Koko, and Okihajime no Muraji Usa.
The other army headed towards Ōmi.
Led by Murakuni no Muraji Oyori, Kakibe no Konemaro, Wani no Omi Kimite, and Ikakawa no Omi Abe, they advanced from Fuwa along the eastern shore of Lake Biwa, aiming for Ōtsu.
The Nihon Shoki records the forces on both sides as numbering “tens of thousands.”
It is impossible to verify the actual numbers of 7th-century armies from rosters or logistical records.
Here, it is sufficient to note that the Nihon Shoki describes them as large forces.
The soldiers marked their clothing with red symbols.
This was a civil war where people from the same regions fought, with little difference in their armor.
The marks were used to distinguish allies during the chaos of battle.
Prince Ōama himself remained in Nogami.
The army heading towards Ōmi was led by Murakuni Oyori, while the Yamato battles were handled by Ōtomo no Fukei, with separate battles beginning in various locations.
The Omi Forces Headed for Fuwa
The Omi court was also gathering a large army.
The troops led by Prince Yamabe, Soga no Karyasu, and Kose no Hito assembled near the Inukami River.
This was around what is now Hikone City.
They were supposed to head towards Fuwa to attack the main forces of Prince Oama.
However, before they could depart, an incident occurred within the army.
Prince Yamabe was killed by Soga no Karyasu and Kose no Hito.
The reason is not recorded in the “Nihon Shoki.”
The army fell into chaos and could not advance. It is said that Soga no Karyasu also took his own life by stabbing his neck after returning from Inukami.
Hata no Ason Yaguni and his son, Otona, also switched sides to support Prince Oama.
The Omi court’s attempt to send forces to Fuwa stumbled significantly at this point.
Meanwhile, in Yamato, the Omi forces were closing in on Prince Oama’s side.
Otomo no Fukei Secures Asuka
The key figure moving in Yamato was Otomo no Fukei.
On June 29, Fukei took control of the Omi court’s military camp in Asuka.
According to the “Nihon Shoki,” Fukei used the information that Prince Takatsu was coming from Fuwa to unsettle the camp, then charged in with about a dozen riders.
Hozumi no Omi Momose, who was involved in conscription on the Omi side, was killed, and Takasaka no O was incorporated into Fukei’s forces.
Gradually, soldiers from around Asuka gathered, and Fukei was appointed as a general by Prince Oama.
Miwa no Kimi Takichi and Kamo no Kimi Ezo also joined.
Although they had secured Asuka, Omi forces were approaching from Kawachi.
On July 1, Fukei deployed troops to the western paths of the Yamato Basin.
At Tatsuta, Sakamoto no Omi Takara and 300 men.
At Osaka, Saji no Kimi Shomaro and several hundred men.
At Ishite Road, Kamo no Kimi Ezo and several hundred men were stationed.
They divided the defense of the routes leading from Kawachi to Yamato.
Records from Nara Prefecture also confirm that Fukei’s forces were positioned on routes like Osaka to meet the Omi army.
The Omi army had already reached Kawachi.
Fukei’s troops, who fought against the forces led by Ikishi no Fumihito, were pushed back.
On the Yamato front, the Omi side took the offensive first.
July 4: A Crushing Defeat at Nara Mountain
Otomo no Fukei moved north of the Nara Basin.
On July 3, he set up camp at Narayama.
Aratao no Ason Akamaro, concerned about the defense of Asuka, advised sending troops back to the old capital.
Fukei sent back Akamaro and Imibe no Omi Koshito, who removed the planks from the roads to use as shields and lined them up at the town intersections.
On the following day, July 4, the Omi forces appeared at Narayama.
They were led by Ono no Kimi Karyasu.
The battle ended in victory for the Omi forces.
The forces under Fukiwake scattered, and Fukiwake himself fled.
The Nihon Shoki clearly states that Ohno no Kayo defeated Fukiwake in this battle.
Kayo pursued the fleeing army southward.
As he advanced to a point where Asuka was visible, he noticed shields standing in various places around the town.
These had been set up earlier by Akamaro and his men.
Kayo, wary of an ambush, withdrew his troops.
There is no record of a large army actually being hidden there.
The Omi forces, victorious at Nara Mountain, halted their pursuit there.
Fukiwake managed to avoid losing Asuka entirely and retreated south to begin gathering his scattered troops.
Tanabe no Kosumi Advances Through the Mountain Paths at Night
The day after Fukiwake’s defeat at Nara Mountain, the Omi forces made their move in the Iga region.
On the night of July 5th.
Tanabe no Kosumi, a commander of the Omi side, crossed the mountains of Kakuma, heading towards Kurareki.
The Nihon Shoki provides a detailed account of this night raid.
Kosumi’s forces furled their banners.
They carried their drums to prevent any sound.
Additionally, they placed “mai” in the mouths of men and horses.
This was to suppress voices and the neighing of horses, allowing the troops to move silently along the mountain paths.
In the dead of night, Kosumi’s forces entered the camp of Tanaka no Omi Ashimaro.
In the darkness, it was impossible to distinguish friend from foe.
Kosumi’s forces used “gold” as their password.
They demanded anyone they encountered to say “gold,” and those who could not were cut down as enemies.
Tanaka Ashimaro realized the password and saved himself by responding “gold” as well.
It was a meticulously planned night raid by the Omi forces.
On the following day, the 6th, Kosumi advanced to Tohagino.
There, Omi no Obito Hino led 3,000 men.
This time, Hino’s forces met Kosumi head-on and pursued him with elite troops.
The Nihon Shoki records that Kosumi escaped alone and did not appear in this area again.
Among the Omi forces, there were commanders capable of disrupting the camps of Prince Oama’s side with night raids.
The tide of the battle began to turn decisively when Murakuni no Oyori continued his advance along the eastern shore of Lake Biwa.
July 7th, Yokokawa at Omi
Murakuni no Oyori and his forces advanced westward from Fuwa.
On July 7th, they clashed with the Omi forces at Yokokawa in Omi.
This location is identified as being around present-day Maibara City in Shiga Prefecture.
The Omi commander was Sakaibe no Muraji Kusuri.
Murakuni no Oyori’s forces emerged victorious, and Sakaibe Kusuri was killed in action.
On July 9th, they fought again at Torikago Mountain.
The exact location remains uncertain, but some theories place it in the mountainous area around Hikone City.
Here, too, Murakuni Oyori’s forces defeated the Omi side and killed Hata Tomotari.
On the 13th, they advanced to the shores of Yasugawa.
Yasugawa corresponds to the present-day Yasu River.
Murakuni Oyori’s forces defeated the Omi army and captured Shatobe no Okuchi and Haji no Chishima.
On the 17th, they attacked the Kurita forces and pursued them southward.
The advance that began at Fuwa moved south along the eastern shore of Lake Biwa, passing through Omi, Torikagoyama, Yasugawa, and Kurita, drawing closer to Otsu.
Meanwhile, the situation in Yamato also began to change.
Reinforcements Arrive for Fukefu Defeated at Narayama
Ōtomo no Fukefu, who had fled from Narayama, retreated southward.
As he reached the vicinity of Sumisaka, forces appeared from the east.
They were led by Okihajime no Utsu, numbering over a thousand horsemen.
Kino no Ahe Maro and others, heading towards Yamato, learned of Fukefu’s defeat and hurriedly dispatched reinforcements.
Fukefu moved to the area around Kanatsuna and regrouped his scattered troops.
At that time, the Omi forces under Ikishi no Kankoku were also entering Yamato via the Osaka Road.
Fukefu turned west to confront them.
The battle took place near Taima.
According to the Nihon Shoki, a soldier named Kurume drew his sword and charged into the enemy lines on horseback.
The cavalry followed, and the Omi forces retreated.
Ikishi Kankoku also fled.
A few days earlier, Fukefu’s forces had suffered losses at Narayama, but with reinforcements from the east, they were able to move again.
The Upper, Middle, and Lower Roads
The battlefield spread across the Yamato Basin.
In the basin, the Upper, Middle, and Lower Roads ran north to south as major routes.
The Omi forces attempted to advance south using these roads.
Prince Ōama’s side stationed troops along each road to intercept them.
On the Middle Road, Inukai no Iokimi of the Omi side gave 200 elite soldiers to Roi no Whale to attack Fukefu’s main camp.
Fukefu had few soldiers at his disposal.
The Nihon Shoki records that Tokumaro and four others, affiliated with Oidera, took up bows and resisted.
Meanwhile, on the Upper Road, Miwa no Kimitakaichimaro and Okihajime no Utsu were fighting the Omi forces.
The location was Hashihaka.
This is around the Hashihaka Kofun in present-day Sakurai City, Nara Prefecture.
Nara Prefecture’s introduction also highlights the battle between Miwa Takachihimaro, Okihajime Utsu’s forces, and the Omi side near Hashihaka during the Jinshin War.
The Omi forces were defeated.
Takaichimaro and Utsu advanced, moving behind Roi no Whale’s forces.
Whale, who was fighting Fukefu’s forces, was attacked from behind, causing his troops to collapse.
Roi no Whale Escapes on a White Horse
Roi no Whale fled on horseback.
The Nihon Shoki notes that the horse was white.
They got stuck in a muddy field and couldn’t move.
Fukiu spotted the fleeing whale and ordered soldiers from Kai Province to give chase.
With pursuers closing in, the whale struck the horse, freeing it from the mud, and managed to narrowly escape.
It’s difficult to take the accounts of heroic deeds and detailed pursuits as literal records of the day. The Jinshin Chronicles often highlight individual acts of bravery.
What can be discerned about the battle is that the forces from Omi were defeated around the Hashiryo area, unable to maintain their advance into Yamato.
At Mount Nara, Otomo no Fukiu was forced to retreat.
Then, reinforcements of over 1,000 cavalry arrived, and as they continued to fight at Taima and Hashiryo, the Yamato front began to recover.
Meanwhile, in Omi, Murakuni no Oyori’s forces continued their push southward.
In both battlefields, the Omi court’s army was starting to be pushed back.
From Yasu River to Kurita
After the Battle of Anokawa on July 13, Murakuni no Oyori’s army continued to advance south.
On the 17th, they attacked the Omi forces at Kurita.
Kurita encompasses the area around present-day Ritto City and Kusatsu City.
Beyond that flowed the Seta River.
Crossing the Seta River would lead them into Otsu.
Nearby was the Omi Otsu Palace, moved there by Emperor Tenji in 667.
The exact location of Otsu Palace was unknown for a long time, but excavations since 1974 have uncovered the southern gate, main hall, rear hall, and corridors in the Nishikori area of Otsu City, revealing the core of the palace.
Murakuni no Oyori’s army was approaching the heart of the Omi court from the east.
Prince Otomo also moved out to Seta.
On July 22, the two armies faced each other across the bridge.
Chison Defends the Seta Bridge
The Omi army set up camp on the west side of the bridge.
Prince Otomo and his retainers were also there.
Chison, tasked with leading the vanguard, prepared traps on the bridge.
The “Nihon Shoki” describes how the central part of the bridge was cut and long planks were laid across.
The plan was to pull a rope to drop enemy soldiers into the river when they stepped onto the planks.
Beyond the planks stood the Omi soldiers.
Arrows flew straight at them.
On the river, there was no room to escape to the sides.
Murakuni no Oyori’s army couldn’t advance forward.
Obito no Kimi Wakaomi discarded his long spear.
He donned layers of armor and drew his sword.
He dashed onto the planks, cutting the rope while taking arrows.
The “Nihon Shoki” depicts him pressing further into the Omi army.
Such focus on the actions of a single warrior may contain the embellishments typical of war chronicles.
The outcome of the battle follows immediately after.
The Omi soldiers defending the bridge fell apart.
Chison cut down the fleeing soldiers, trying to rally them back to the camp.
There was no stopping it.
Chison was also killed near the bridge.
Prince Otomo and the ministers on his left and right departed from Seta.
The forces led by Murakuni Oyori crossed the bridge and advanced to the vicinity of Awazuoka.
They had reached the south of Otsu Palace in Omi.
The Otsu City Museum of History also positions the Battle of Seta Bridge as a decisive moment leading to the conclusion of the Jinshin War.
July 23: The Final Moments of Prince Otomo
The following day, the 23rd.
Murakuni Oyori and his men defeated Inukai no Ikimi and Tani no Naoshite in Awazushi.
Ikimi was a figure who had also led the Omi forces in the Yamato region.
The forces of the Omi court scattered, and people began to leave Prince Otomo’s side.
According to the Nihon Shoki, only Mononobe no Maro and one or two attendants remained loyal to the end.
Prince Otomo fled to the mountains.
There, he took his own life.
He was in his 25th year.
The exact location referred to as “the mountains” is not determined.
There are theories placing it around Oyamazaki in the Otokuni District of Yamashiro Province, or near Otsu, but pinpointing the exact modern location of Prince Otomo’s death remains challenging.
In Meiji 3 (1870), Prince Otomo was posthumously given the title “Emperor Kobun.”
The Nihon Shoki does not record Prince Otomo’s ascension to the throne, leading to long-standing debates about his status in 672.
This article uses the name Prince Otomo as it was used during the war.
The End of the Battle in Yamato
On July 22, when the battle at Seta Bridge took place, military actions in Yamato were also reaching their conclusion.
After pacifying Yamato, Otomo no Fukei crossed Osaka and headed for Naniwa.
Other commanders advanced north along the Upper, Middle, and Lower Roads, reaching the mountains.
Fukei entered Naniwa’s Ogori and compelled the provincial governors of the western provinces to surrender their official keys, station bells, and seals of authority.
The official keys managed the government’s warehouses.
The station bells and seals of authority were related to the rights to use the official transportation system.
Alongside the military victories on the battlefield, the control over regional administration and transportation held by the Omi court began to shift to Prince Oama’s side.
On the 24th, commanders from various fronts gathered in Omi.
On the 26th, Prince Otomo’s head was transported to Fuwa and delivered to Prince Oama.
When Prince Oama left Yoshino on June 24, there were just over twenty men by his side.
In just over a month,
the main battles of the Jinshin War had concluded.
The Defeated of the Omi Court
In August, Prince Oama proceeded with the punishment of those who had served the Omi court.
The Right Minister, Nakatomi no Kamiko, was executed at Tane in Asai.
The Left Minister Soga no Akane, Kose no Hito and his descendants, and Nakatomi no Kane no Ko, along with the children of the already deceased Soga no Kadayasu, were exiled.
Many others were pardoned.
Those who fought on the side of Prince Oama were rewarded.
Murakuni no Oyori, Otomo no Fukei, Ki no Ahema, Okihajime no Usagi, and Tahinaji.
The people who led troops in Mino, Ise, Iga, Yamato, and Omi joined the new government.
On September 8, Prince Oama departed from Fuwa.
He traveled westward through Kuwana, Suzuka, Ahe, and Nabari.
This was the same route he had taken when he left Yoshino in June.
On the 12th, he returned to Asuka.
That winter, he moved to the Asuka Kiyomihara Palace.
In February of the following year, 673, Prince Oama ascended to the throne.
He became Emperor Tenmu.
The political center, which Emperor Tenji had moved to Omi, returned to Asuka.
Nine years had passed since the Battle of Baekgang.
After experiencing defeat on the Korean Peninsula and the internal strife at the end of the Tenji administration, the era of Emperor Tenmu began.
Following this, under Emperor Tenmu and Princess Uno Sarara, later Empress Jito, movements towards reforms in government administration, imperial family order, legal systems, capital cities, and historical compilation progressed.
The names of those who fought in the Jinshin War, such as Murakuni no Oyori and Otomo no Fukei, were preserved in the memory of this new regime.
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The book ‘Baekgang: Ancient Japan’s Control of the Korean Peninsula and Its End’ covers the relationships between Baekje, Silla, Goguryeo, and the Wa nation, the Baekje Restoration War, the Battle of Baekgang in 663, and the subsequent state of the Wa nation.
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Baekgang: Ancient Japan's Control of the Korean Peninsula and Its End [ Ohira Hiroshi ]
