Bottle No. 4 – Prince Kusakabe and the Jinshin Rebellion
Introduction
In this essay, I would like to focus on Prince Kusakabe.
Yet, everything about him—from his birth to his death—remains shrouded in mystery.
Hardly any concrete clues survive that might help us unravel his life.
To speak of him, therefore, is to say, I think this may be so, or perhaps it was like this.
What follows is an attempt to piece together a portrait of Prince Kusakabe, relying on the few faint traces that remain and filling the gaps with reasoned imagination.
I ask for the reader’s understanding as you accompany me through this exploration.
1. The Birth of Prince Kusakabe
It is generally said that Prince Kusakabe was born in the first year of Emperor Tenchi’s reign (662 CE) as the second son of Prince Ōama, later Emperor Tenmu.
However, in 662 CE Prince Ōama was in Kyushu—at the frontline base in Fukuoka—together with his elder brother, Prince Naka no Ōe (later Emperor Tenchi), leading the expedition to rescue the fallen kingdom of Baekje.
At that time, the Korean Peninsula stood at the close of its Three Kingdoms period—Silla, Goguryeo, and Baekje.
The Tang Empire, which had overthrown the Sui, sought to subdue Goguryeo, while Silla aimed to destroy Baekje and unify the peninsula.
Thus, the Tang–Silla alliance was formed, and backed by Tang’s overwhelming power, Silla launched its assault upon Baekje.
Responding to Baekje’s plea for help, Empress Saimei decided to send troops.
She herself, accompanied by her sons—Prince Naka no Ōe and Prince Ōama—led an army of some 27,000 men to Fukuoka.
Prince Ōama was joined by his principal consort, Princess Ōta.
It is said that while en route, at Ōhako in Bizen Province (around present-day Kurashiki, Okayama Prefecture), Princess Ōta gave birth to their daughter, Princess Ōku, on February 12, 661 (1st month 8th day of Saimei 7).
The following year, in 663 (2nd year of Tenchi), while stationed at Natsuno-Ōtsu—modern-day Natsu in Fukuoka Prefecture—Princess Ōta gave birth to a son who was named Prince Ōtsu after that place.
It is said that the year before, in 662, Prince Kusakabe had already been born.
His mother, Princess Unonosarara (hereafter referred to simply as Princess Uno), was Princess Ōta’s younger sister; both sisters were married to Prince Ōama.
Yet Princess Uno seems not to have accompanied him to the Kyushu front.
There is no record—not even a passing mention—of her presence in Fukuoka, nor of any childbirth there.
In contrast, the births of both Princess Ōku and Prince Ōtsu are clearly recounted, each with its setting and circumstances along the expedition route.
But for Prince Kusakabe there is complete silence—not only about his birth, but about his mother’s whereabouts at that time.
From this, one can only conclude that Princess Uno remained behind in Asuka, serving as the guardian of the royal residence.
In other words, it seems impossible that Prince Kusakabe could have been born in 662.
When, then, was he actually born?
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Nikitatsu / Dōgo Hot Spring
(Matsuyama, Ehime Prefecture) |
The Seto Inland Sea before reaching Kyushu / Distant silhouettes of islands near Suō-Ōshima |
2.From the Defeat at Baekgang to the Move to Ōmi
Let us turn back the clock for a moment.
It is said that on January 6, 661, Empress Saimei and her court set sail from Naniwa Port to aid Baekje.
The following poem, composed by Nukata no Ōkimi—the beloved of Prince Naka no Ōe, who accompanied him on this campaign—was written on January 14, while their fleet waited for the tide at Nikitatsu (present-day Dōgo Hot Spring in Matsuyama, Ehime Prefecture):
At Nikitatsu we wait for the moon
To embark upon our voyage—
Now the tide has turned,
Let us row forth.
On February 12 of that same year, at Ōhako Bay in Bizen Province (around modern Ushimado in Kurashiki, Okayama Prefecture), Princess Ōta gave birth to Princess Ōku.
It seems the party stayed there for a while so that she could recuperate.
By March 25, they had reached Natsuno-Ōtsu (today’s Natsu in Fukuoka Prefecture), and by May had moved to the provisional palace of Asakura Tachibana no Hiro-niwa, preparing for the campaign to restore Baekje.
Perhaps due to the rigors of the journey, Empress Saimei passed away on August 24—three months later—before the battle at Baekgang even took place. She died with full confidence that victory was near.
Crown Prince Naka no Ōe went into mourning.
Her remains were brought back to Naniwa Port on October 23 of that year and laid in temporary repose on the riverbank at Asuka on November 7.
Thus the year 661 came to a hurried close.
When the new year of 662 dawned, Crown Prince Naka no Ōe still did not ascend the throne.
Instead, he continued to direct operations from the front as commander-in-chief of the Baekje restoration army.
It is said that Prince Kusakabe was born in this year.
Yet, as noted in the previous section, Princess Ōta, Prince Ōama’s principal wife, had accompanied him to Fukuoka, while Princess Uno—the supposed mother of Kusakabe—appears nowhere in the records.
It seems unlikely that she was present at the Kyushu front.
Therefore, the birth year of 662 may well have been retroactively assigned later, when Prince Kusakabe was made crown prince under Emperor Tenmu.
Then came the defeat at the Battle of Baekgang in October 663.
Baekje was utterly destroyed, and there arose the real fear that the Tang–Silla allied forces might invade the Japanese homeland next.
To prepare for this, Crown Prince Naka no Ōe ordered the rapid construction of defensive fortifications—Mizuki, Ōnojō, and Kii Castle among them—and remained in Dazaifu to oversee their reinforcement.
Assisting his brother in stabilizing Kyushu’s defenses, Prince Ōama likely returned to Asuka only after the situation had settled, probably in early 664.
It had become customary for a new emperor to establish a new capital upon accession, and thus the transfer of the capital to Ōmi was a natural step.
Still, moving to Shiga—deep inland—seems to have been a precaution against possible invasion from Tang and Silla.
Construction of the new capital proceeded at remarkable speed, and by April 667 the move was completed.
In February of the following year, 668, Prince Naka no Ōe ascended the throne as Emperor Tenchi.
Returning now to our main subject:
Prince Kusakabe was likely born not in 662 but sometime between Prince Ōama’s return to Asuka in 664 and the subsequent transfer of the capital.
At the earliest, his birth would have been in the autumn of 664—making him not one year older but rather one year younger than Prince Ōtsu.
At that stage, such a difference in age probably carried little significance.
Yet it would later become a matter of consequence—when Prince Ōama ascended as Emperor Tenmu and named Kusakabe his crown prince, and even more so after Emperor Tenmu’s death—forcing later compilers of the Nihon Shoki to revise the chronology to preserve imperial legitimacy.
3. The Jinshin Rebellion
When Emperor Tenchi ascended the throne, Prince Ōama was named Crown Prince (more precisely, Crown Younger Brother ).
At that point, there should have been no doubt that the next emperor would be Prince Ōama.
However, the presence of Emperor Tenchi’s son, Prince Ōtomo, cast a long shadow over this succession.
In those days, emperors customarily had multiple wives in order to ensure the continuity of the imperial line.
The structure was even codified in the early ritsuryō system.
It defined the ranks of imperial consorts as follows:
- Kōgō (Empress) – the principal wife of the emperor; in principle, there was only one.
- Hi (Consort) – up to two, chosen from imperial princesses of the fourth rank (shihon) or higher.
- Bunin (Lady) – up to three, chosen from the daughters of ministers or nobles of the third rank.
- Hin (Concubine) – up to four, chosen from the daughters of nobles of the fourth rank or above.
In addition to these, during the Asuka period, there was a practice in which provincial chieftains offered their daughters to the court as uneme (court attendants).
Prince Ōtomo’s mother, Iga no Uneme Yakako no Iratsume, was one such uneme—a woman of provincial noble birth rather than of imperial lineage.
This meant that her son Ōtomo, though the emperor’s child, stood far down the line of succession and could not rightfully inherit the throne unless extraordinary circumstances arose.
Emperor Tenchi ascended in January 668, likely in his early forties.
Until then, he seems to have been a man guided more by reason than by emotion.
Yet once enthroned—and as the domestic and international situations around Japan temporarily stabilized—he appears to have relaxed his vigilance and grown more sentimental toward his own kin.
Three years later, on December 3, 671, Emperor Tenchi passed away.
The previous year, he had created the post of Daijō Daijin (Chancellor of the Realm)—the first in history—and appointed his son Ōtomo to that position.
In 671, when he fell gravely ill, he summoned Prince Ōama to his bedside and entrusted him with the affairs of state.
However, according to tradition, a plot to assassinate Prince Ōama had already taken shape.
Sensing the danger, Prince Ōama renounced his position as Crown Prince on the spot, took Buddhist vows, and fled to the mountains of Yoshino.
To the courtiers and powerful clans surrounding the throne, the rightful successor was clearly Prince Ōama.
It seemed unnatural that Ōtomo—whose mother was not of imperial blood—should ascend instead.
This perception, more significant than modern readers may imagine, explains why, after Emperor Tenchi’s death, when Prince Ōama raised troops, few regarded it as rebellion.
Rather, it was seen as an inevitable correction of order.
Supporters rallied not only from provincial clans but even from within the court at Ōtsu itself.
When Prince Ōama left Yoshino and began his march eastward, his party numbered fewer than a hundred.
Yet in a matter of days, it swelled into an army of tens of thousands—proof of how widespread the sympathy for his cause was.
There is no need here to recount the detailed course of the Jinshin Rebellion.
Suffice it to say that it ended in Prince Ōama’s overwhelming victory.
He ascended the throne as Emperor Tenmu and carried out sweeping reforms—centralizing power around the emperor in continuation of the Taika Reforms.
In doing so, Emperor Tenmu relied not so much on senior courtiers or powerful nobles, but on his own family: his empress, Uno no Sarara (later Empress Jitō), and their sons—Prince Takachi, Prince Ōtsu, and Prince Kusakabe.
Yet this very reliance on blood ties would, in time, become the seed of the next tragedy.
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| Site of the Ōmi Ōtsu Palace at Nishikori (Ōtsu City, Shiga Prefecture) |
4. The Four Children of Emperor Tenmu
The Jinshin Rebellion lasted less than a month—from July 24 to August 21, 672 CE.
Its course, in brief, unfolded as follows:
- July 24: Prince Ōama escaped from Yoshino.
- July 31: His forces entered Mino Province, gathered troops from the eastern regions, and split into two armies—one directed toward Yamato (the old capital of Asuka), the other toward Ōmi.
That same day, Ōmi’s forces also marched out toward Fuwa.
- August 8: The first battle was fought at Yokokawa in Omi’s Osagano region. Prince Ōama’s troops won successive victories thereafter, including the Battle of Hashiraka (near the Hashihaka Kofun), pressing their advance.
- August 20: The Ōmi court army suffered a crushing defeat at the Battle of Seta Bridge.
- August 21: Prince Ōtomo took his own life by hanging at the age of twenty-four, and the rebellion came to an end.
At the time of the rebellion’s conclusion, Emperor Tenmu’s principal children were still very young.
Princess Tōchi, who had become the wife of Prince Ōtomo, was about nineteen to twenty-four years old.
Prince Ōtsu was nine, his elder sister Princess Ōku was eleven, and Prince Kusakabe perhaps eight.
The eldest among them, Prince Takachi, was eighteen and distinguished himself in battle during the rebellion.
Princess Tōchi is remembered as Prince Ōtomo’s consort on the Ōmi side, but as for the younger ones—Ōtsu, Ōku, and Kusakabe—no records exist.
We know neither where they were sheltered during the conflict nor whether they accompanied the campaigns at all.
Here I must indulge in speculation.
When Prince Takachi fled from the capital at Ōtsu, might he have taken these three young children with him?
If so, once they were safely out, and with no time to lose before joining his father’s army, he may have hidden the children somewhere secure—perhaps in the old capital of Asuka.
In Asuka stood Yamada-dera, a temple originally commissioned by Soga no Kurayamada Ishikawa no Maro.
Construction had been halted when its founder was forced to commit suicide under charges of treason, but the project was later resumed during Emperor Tenchi’s reign.
I sense that this resumption was closely connected with Princess Uno, Prince Kusakabe’s mother.
It may be that Prince Takachi hid the three children at Yamada-dera and entrusted the defense of Asuka to Ōtomo no Fukei, a general loyal to Prince Ōama.
As a result, Asuka was captured with little resistance—almost effortlessly.
However, the Ōmi forces, determined to retake the old capital, sent a massive army from Naniwa.
They vastly outnumbered Ōtomo no Fukei’s troops and soon overwhelmed them.
Learning of this, Prince Ōama divided his forces: one to continue the advance toward Ōmi, and another to join Fukei’s army to repel the enemy approaching Asuka from Naniwa.
The decisive battle over Asuka was fought at Ashiike—perhaps the present-day Yoshigaike Pond in Kashiba City.
The conscripted Ōmi soldiers were poorly motivated, and once again, Ōtomo no Fukei’s troops, fighting under Prince Ōama’s banner, won a sweeping victory.
Thus, Asuka was spared the ravages of war.
Yet behind these struggles for the old capital, one cannot help but sense the hidden presence of Prince Ōama’s three young children.
These were the children who survived the Jinshin Rebellion:
Prince Takachi (eighteen), who protected and concealed them; Princess Ōku (eleven); Prince Ōtsu (nine); and Prince Kusakabe (eight).
It is not difficult to imagine the deep bond of unity that grew among the four of them through those perilous days.
And it was these four—bound by that shared experience—who would go on to support Emperor Tenmu’s new order as the princes and princesses of the restored imperial line.
Yet they were also the ones who, after his death, became the sacrifices demanded to preserve that very system.
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Area around Yoshigaike and Chimataike Ponds — identified with Ashiike, the site of the Battle for Asuka during the Jinshin Rebellion
(Kashiba City, Nara Prefecture) |
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Ōsaka area — believed to have been the
encampment of Ōtomo no Fukei’s forces
(Kashiba City, Nara Prefecture) |
Site of the Asuka Kiyomihara Palace
(Asuka Village, Takaichi District, Nara Prefecture) |
Ruins of Yamada-dera Temple, associated with
Soga no Kurayamada Ishikawa no Maro
(Asuka Village, Takaichi District, Nara Prefecture) |
Thus concludes this account.
The continuation of this story will appear in
Bottle No.5: “The Children of Emperor Tenmu and the Sun Goddess Amaterasu.”