November 3, 592, the fifth year of Emperor Sushun‘s reign.
Soga no Umako addressed the assembled courtiers.
“Today is the day we present tribute from the eastern provinces to the Emperor.”
The courtiers gathered.
It was then that Umako ordered Otomo no Komaro to assassinate Emperor Sushun.
The “Nihon Shoki” records the events of this day with surprising brevity.
The Emperor was buried at Kurahashioka no Misasagi on the same day.
Emperor Sushun’s reign ended after about five years.
The executioner was Otomo no Komaro.
And the “Nihon Shoki” names Soga no Umako, a minister of the court, as the one who ordered the assassination.
The Emperor was not killed in a battle against powerful clans.
According to the “Nihon Shoki,” it was a minister at the heart of court politics who planned and had the Emperor killed.
Why did such an event occur?
To understand the relationship between Emperor Sushun and Umako, we need to look back to the Jinshin Rebellion five years earlier.
After Mononobe no Moriya’s Death, Prince Hasebe Ascends the Throne
In April of the second year of Emperor Yomei’s reign (587), Emperor Yomei passed away.
The struggle for succession and the conflict between the Soga and Mononobe clans over the acceptance of Buddhism shook the court significantly.
Soga no Umako first killed Prince Anahobe, who was allied with Mononobe no Moriya.
Then in July, Umako led princes and powerful clans against Mononobe no Moriya.
This was the Jinshin Rebellion.
Moriya resisted from his stronghold in Shibukawa District, Kawachi Province.
The Mononobe forces were strong, and the “Nihon Shoki” tells us that Umako’s side was repeatedly repelled.
During the battle, Prince Shotoku created images of the Four Heavenly Kings and vowed to build a temple and pagoda if victorious.
Umako also vowed to establish a temple.
Eventually, Tomi no Ichii shot Moriya, who was directing from a tree, and the Mononobe forces collapsed.
Moriya was killed in battle.
The Mononobe clan, which had long been responsible for the court’s military affairs, suffered a significant loss of power here.
After the battle, Prince Hasebe ascended the throne.
He became the 32nd Emperor, Emperor Sushun.
His father was Emperor Kinmei.
His mother was Soga no Oane no Kimi, making him related to Soga no Umako through his maternal line.
Even after Emperor Sushun’s ascension, Umako remained a minister at court.
Having defeated Mononobe no Moriya, Umako continued to stand at the center of politics.
Kurahashi Palace and Hokoji Temple
Emperor Sushun established his palace at Kurahashi.
This is near present-day Sakurai City, Nara Prefecture.
One of the major projects undertaken during his reign was the construction of Hokoji Temple.
This temple is connected to what is now known as Asuka-dera.
In the first year of Emperor Sushun’s reign (588 AD), a group of artisans, including the monk Hyeja from Baekje, along with temple builders, metalworkers, tile experts, and painters, arrived in Japan.
That same year, Umako demolished the house of Kinunui no Miyatsuko no Yatsuka in Asuka and began the construction of the Hokoji Temple.
This project aimed to build a temple with a full-scale temple complex in Japan, inviting skilled workers from Baekje to achieve this goal.
In the 587 AD conflict known as the Battle of the Year of the Fire Sheep, the rivalry between the Soga and Mononobe clans also involved a clash over Buddhism.
The year after Moriya’s death, Umako advanced the construction of a great temple.
In October 592, the construction of the Buddha Hall and corridors of Hokoji Temple began, as recorded in the Nihon Shoki.
In that same month, an incident occurred between Emperor Sushun and Umako.
However, before discussing that, there is another point to consider.
Towards the end of Emperor Sushun’s reign, the court mobilized an army exceeding 20,000 troops.
In 591, Over 20,000 Troops Headed to Tsukushi
In the fourth year of Emperor Sushun’s reign (591 AD), in August, the emperor gathered his ministers and asked them.
“I wish to reestablish Mimana. What are your thoughts?”
According to the Nihon Shoki, the ministers agreed with the emperor’s proposal.
On November 4th, the court actually mobilized the army.
Kinoomaro no Sukune, Kose no Saru no Omi, Otomo no Kune no Muraji, and Katsuragi no Unara no Omi.
These four were appointed as generals, and the ministers and clan leaders were organized as vice-generals and troops.
The Nihon Shoki records the military strength as,
over 20,000.
The troops advanced to Tsukushi in Kyushu and waited there.
At the same time, Kishi no Kane was sent to Silla, and Kishi no Mokurenko to Mimana, to investigate the situation regarding Mimana.
However, it was not the case that 20,000 troops crossed to the Korean Peninsula to start a war.
The army remained in Tsukushi.
Nevertheless, according to the Nihon Shoki, a large-scale military mobilization involving several powerful clans as generals was underway at the end of Emperor Sushun’s reign.
This army was still in Tsukushi when Emperor Sushun died.
Thus, the year 592 began.
Emperor Sushun and the Boar’s Head
On October 4th, in the fifth year of Emperor Sushun’s reign (592 AD), a mountain boar was presented to the emperor.
According to the Nihon Shoki, Emperor Sushun pointed to the boar and said,
When will I be able to cut down those I despise, just as I would cut off this boar’s head?
He did not name anyone specifically.
Yet, the Nihon Shoki places another entry immediately after this.
It reports that the emperor had prepared numerous weapons and was behaving unusually.
Six days later.
On October 10th, Umako took action.
Umako, fearing that he was the one despised by the emperor, gathered his allies and plotted to assassinate the emperor.
The main text of the Nihon Shoki records the events in this order.
The emperor’s remark upon seeing the boar. The weapons gathered at the court. The fear of Umako.
And then, the assassination plot.
However, the Nihon Shoki also preserves another tradition.
Was it Otomo no Koteko who informed Umako?
Emperor Sushun had a consort named Otomo no Koteko.
She was the daughter of Otomo no Nukateko and is said to have borne Prince Hachiko and Princess Nishikiyo with Emperor Sushun.
According to a story recorded as “another account” in the Nihon Shoki, Koteko resented the waning of the emperor’s affection.
So, she sent someone to Umako, conveying the emperor’s demeanor.
When a mountain boar was presented, the emperor spoke of beheading it.
Additionally, weapons were being actively manufactured at the court.
Hearing this, Umako was taken aback.
The main text and “another account” in the Nihon Shoki differ on how Umako learned of the emperor’s remarks.
It cannot be confirmed whether Koteko’s betrayal actually occurred.
Yet, the two traditions preserved in the Nihon Shoki share common elements.
In the autumn of 592, Emperor Sushun made remarks indicating he harbored strong animosity towards someone, and weapons were being gathered at the court.
Umako perceived these actions as a threat to himself.
About three weeks later, the emperor was killed.
November 3rd—”Today, we present the tribute from the eastern provinces”
On November 3rd of the fifth year of Emperor Sushun’s reign, Umako informed the court ministers.
Today, the tribute from the eastern provinces will be presented to the emperor.
The tribute, or chō, consisted of offerings made to the court from various regions.
With a presentation ceremony, it would not be unusual for the court ministers to gather before the emperor.
The Nihon Shoki notes that Umako “deceived” the court ministers.
He used the tribute from the eastern provinces to create an opportunity to assassinate the emperor.
The person chosen to carry out the act was Higashi no Hanano Atai Komako.
The Higashi no Hanano clan was known as a clan of foreign origin, serving the Yamato court centered in Asuka.
Komako, acting on Umako’s orders, assassinated Emperor Sushun.
The Nihon Shoki does not detail what weapon was used, how many were involved in the attack, or whether the emperor resisted.
The account is succinct.
Umako deceived the court ministers.
He ordered Higashi no Hanano Atai Komako.
Komako killed the emperor.
It is not possible to expand this into a detailed battle scene.
And in the same day’s entry, there is one more line.
Emperor Sushun was buried at Kurahashioka Mausoleum.
The Emperor Buried on the Day He Was Killed
The Nihon Shoki records that Emperor Sushun was buried on the same day he was assassinated, November 3rd.
His tomb is known as the Kurahashioka Tomb.
This is in the same region where his palace was located.
In ancient times, it was not always the case that an emperor was immediately buried upon death.
The Nihon Shoki contains numerous examples of emperors being laid to rest only after a period called “mourning.”
However, there is no mention of such a period in the account of Emperor Sushun.
Assassination. And burial on the same day.
From the description in the Nihon Shoki, it seems the matter was handled with unusual swiftness.
What is even more striking is that there is no record of Umako, who is clearly stated to have ordered the emperor’s assassination, being punished for this incident.
Umako continued to serve as a minister in the court’s politics.
If we take the Nihon Shoki’s account of the assassination at face value, it suggests that Umako ordered the emperor’s killing without losing his position.
This raises the question of whether the assassination of Emperor Sushun was a secret plot by Umako alone, or to what extent other influential figures were involved, a topic that has been debated in historical research.
It is impossible to reconstruct the full picture from the historical sources.
However, the Nihon Shoki does not leave the mastermind of the assassination ambiguous.
It states, “Umako no Sukune deceived the courtiers,”
and continues, “He had Higashi no Hanano Atai Komano kill the emperor.”
Even with the Emperor’s Death, Over 20,000 Troops Remained in Tsukushi
Two days after the assassination, on November 5th,
a fast messenger was dispatched from the court to Tsukushi.
The more than 20,000 troops sent there in November of the previous year were still stationed there.
The orders conveyed to the generals are recorded in the Nihon Shoki as follows:
“Do not neglect external affairs due to internal strife.”
This was immediately after the emperor’s assassination.
Yet, the troops in Tsukushi were ordered to continue their mission concerning the Korean Peninsula.
The Nihon Shoki does not specify who made this decision.
Even with Emperor Sushun’s death, the court’s functions did not cease, and the system for delivering orders to the troops deployed in the provinces was maintained.
The fact that the Nihon Shoki refers to Emperor Sushun’s death as “internal strife” is also noteworthy.
On November 3rd, the emperor was killed, and by the 5th, a messenger had been sent to Tsukushi.
From this, it is evident that the court swiftly moved on to the next phase of politics following the assassination.
The Assassin, Higashi no Hanano Atai Komano, Was Also Killed
Higashi no Hanano Atai Komano, who killed Emperor Sushun, did not live long afterward.
According to the Nihon Shoki, Komano secretly took Soga no Umako’s daughter, Kawakami no Iratsume, and made her his wife.
Initially, Umako believed his daughter had died.
Eventually, it was discovered that Komano had a relationship with Kawakami no Iratsume.
Umako killed Komano.
Thus, the executor of Emperor Sushun’s assassination disappeared within the same month.
The reason for the killing of Komako, as recorded in the Nihon Shoki, was not to silence him over the assassination of Emperor Sushun.
It was written as a punishment for taking Kawakami no Musume.
It can also be viewed as a silencing act.
As a result, the person who directly killed Emperor Sushun was soon killed as well.
Only Umako remained at the center of politics.
After Emperor Sushun’s Death, Empress Suiko Ascends the Throne
After Emperor Sushun’s death, the throne was taken by Toyomike Kashikiya Hime no Mikoto.
She was the empress of Emperor Bidatsu and the half-sister of Emperor Sushun.
She later became known as Empress Suiko.
In the first year of Empress Suiko’s reign (593), Prince Umayado became the Crown Prince and joined the political scene.
And Soga no Umako remained as a minister.
The person named in the Nihon Shoki as the killer of Emperor Sushun continued to serve as a minister under the new emperor.
During the Suiko era, the construction of Hoko-ji Temple progressed, envoys were sent to the Sui dynasty, and policies like the Twelve Level Cap and Rank System and the Seventeen-Article Constitution, known to later generations, were implemented one after another.
Umako remained at the center of politics until his death in the 34th year of Empress Suiko’s reign (626).
The assassination of Emperor Sushun did not lead to the downfall of the Soga clan.
November 3, 592.
Umako gathered the court officials under the pretext of presenting tribute from the eastern provinces and had Higashi no Ayahito no Komako kill the emperor.
The entry left by the Nihon Shoki is brief.
Even so, by tracing the dates before and after the assassination, the outline of the incident becomes quite clear.
In November 591, an army of over 20,000 headed to Tsukushi.
On October 4, 592, Emperor Sushun, upon seeing a boar, remarked, “I wish to cut off the head of the one I hate.”
On October 10, Umako planned the assassination of the emperor.
On November 3, Higashi no Ayahito no Komako killed Emperor Sushun.
The emperor was buried at Kurahashioka Tomb on the same day.
On November 5, an order was sent to the general in Tsukushi, “Do not neglect external affairs due to internal strife.”
And the following year, 593, Empress Suiko ascended the throne.
Umako, who was recorded as having killed Emperor Sushun, stood as a minister in the new court.
