Fukushima Masanori: From Toyotomi Loyalist to Tokugawa Target—The Life and Tragic End of a Military Faction Leader

Introduction

A military commander who lost a prized family heirloom spear at a drinking party and fell from 500,000 koku to 45,000 koku due to the unauthorized repair of his castle—.
When we talk about Fukushima Masanori, we often focus on these kinds of "failure stories."
However, if we carefully trace his life, a deeper historical drama emerges from the transition period between the Sengoku and Edo periods.

Fukushima Masanori achieved the feat of being the first to strike in the Battle of Shizugatake, fought as a vanguard for the Eastern Army at Sekigahara, and managed his domain in Hiroshima with great skill.
Why, then, did he have to be purged by the Tokugawa Shogunate? In this article, we will look at how a commander who possessed not only martial prowess but also talent as a ruler was tossed about by the turning point of the era.

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Table of Contents

1. As Toyotomi Hideyoshi's Cousin: From Childhood to Shizugatake

2. The Military Faction and the Civil Faction: Cracks Within the Toyotomi Regime

3. The Decision at Sekigahara: The Ironic Result of "Hatred for Mitsunari"

4. As Lord of Hiroshima Domain: From Commander to Ruler

5. The Blunder of a Heavy Drinker: The Anecdote of the Famous Spear "Nihongo"

6. The Road to Forfeiture: The Ruin Brought by the Repair of Hiroshima Castle

7. The End in Shinano: A Commander's Quiet Final Years

8. The Tragedy of Standing at a Turning Point in History

1. As Toyotomi Hideyoshi's Cousin: From Childhood to Shizugatake

In 1561, Fukushima Masanori was born in Kaito District, Owari Province (present-day Ama City, Aichi Prefecture).
His father is said to be Fukushima Masanobu, who ran a cooperage, but there is also a theory that his biological father was Hoshino Narimasa, leaving some uncertainty about his origins.
However, what is certain is the blood relationship that his mother was an aunt of Toyotomi Hideyoshi.

Because of this connection, Masanori, whose childhood name was Ichimatsu, served as a page to Hideyoshi from a young age.
Raised as a close aide to Hideyoshi alongside Kato Kiyomasa, Masanori made his battlefield debut in 1578 at the age of 18 during the siege of Miki Castle in Harima Province.
In this battle, he achieved the feat of killing two enemy commanders and was granted a stipend of 200 koku.

It was the Battle of Shizugatake in April 1583 that made Masanori's name known throughout the land.
After the death of Oda Nobunaga, Hashiba Hideyoshi and Shibata Katsuie clashed over the succession.
In this battle that would decide the fate of the nation, Masanori achieved the distinction of being the "first to strike" by killing the enemy commander Haigo Ieyoshi.
For this achievement, while the other six spears received rewards of 3,000 koku, Masanori was granted an exceptional 5,000 koku.

However, the term "Seven Spears of Shizugatake" itself became established only after the Edo-period "Taikoki" (by Oze Hoan, 1625) and cannot be confirmed in primary sources from that time.
Even so, it is an undeniable fact that this battle was the catalyst for Masanori's rise to prominence.

Afterward, Masanori participated in all of Hideyoshi's major battles, including the Battle of Komaki and Nagakute, the pacification of Shikoku, the pacification of Kyushu, and the Siege of Odawara, and in 1587, he was appointed as a daimyo of 110,000 koku in Imabari, Iyo Province.
Furthermore, in 1595, he became the lord of Kiyosu Castle in Owari Province with 240,000 koku, growing into a core figure within the Toyotomi retainer group.

2. The Military Faction and the Civil Faction: Cracks Within the Toyotomi Regime

Within the Toyotomi administration, there were two distinct groups: the 'Military Faction' (Budan-ha), which prioritized battlefield achievements like Masanori and Kato Kiyomasa, and the 'Civil Faction' (Bunji-ha), which handled administration and logistics like Ishida Mitsunari and Mashita Nagamori.
However, this dichotomy is a later historical construct, and it is not recorded as a clear factional conflict in primary sources from that time.

Nevertheless, it is certain that the dispatch of troops to Korea during the Bunroku-Keicho campaigns (1592-1598) made the conflict between these two factions decisive.
The military commanders, who were risking their lives on the front lines, held strong dissatisfaction with the decisions made by Mitsunari and his associates, who were in charge of logistics and reporting on the war situation from the rear.
In particular, during the Battle of Ulsan (December 1597 to January 1598), the military inspector Fukuhara Nagataka (Mitsunari's brother-in-law) and others reported to Hideyoshi that 'the two commanders Hachisuka and Kuroda did not engage in battle,' leading to Hachisuka Iemasa being ordered to confine himself to his domain.

The fury of the Military Faction against this unfair punishment was suppressed while Hideyoshi was alive, but it surfaced all at once after his death in August of the third year of the Keicho era (1598).

In the intercalary third month of the fourth year of the Keicho era (1599), when Maeda Toshiie, the balancer of the Toyotomi administration, passed away, an incident occurred the very next day.
An incident occurred in which seven generals, including Masanori, attacked or sought to prosecute Ishida Mitsunari.
Recent research suggests that this incident was not an 'armed attack' but rather a 'litigation disturbance' seeking sanctions or seppuku for Mitsunari.

The person who settled this disturbance was Tokugawa Ieyasu, the head of the Council of Five Elders.
Ieyasu took on the role of mediator and resolved the matter by having Mitsunari retire and move to Sawayama Castle.
This led to a political rapprochement between the Military Faction and the Tokugawa clan.
However, for Ieyasu, this was also a perfect opportunity to bring the Toyotomi-loyalist commanders into his own camp.

3. The Decision at Sekigahara: The Ironic Result Invited by 'Hatred of Mitsunari'

In June of the fifth year of the Keicho era (1600), when Tokugawa Ieyasu headed to Aizu to subjugate Uesugi Kagekatsu, Ishida Mitsunari took advantage of his absence to raise an army.
Upon receiving this news in Oyama, Shimotsuke Province, Ieyasu declared to the various commanders that he would 'defeat the rebel Ishida Mitsunari.'

It is said that at this 'Council of Oyama,' Fukushima Masanori was the first to express his support for Ieyasu.
While there is debate in recent years regarding the actual existence of this meeting, it is an undeniable fact that Masanori sided with the Eastern Army (the Tokugawa side).

Masanori's decision was heavily influenced by his grudge against Mitsunari dating back to the Korean campaigns. Kuroda Nagatomo had persuaded him by saying, 'This battle is not to draw a bow against the Toyotomi family, but to defeat Mitsunari,' and it is believed that Masanori himself held the conviction that 'eliminating Mitsunari is for the sake of the Toyotomi family and Lord Hideyori.'

In the main Battle of Sekigahara on September 15, Masanori led about 6,000 soldiers and served as the vanguard of the Eastern Army.
Although there was an incident where Ii Naomasa and Matsudaira Tadayoshi took the vanguard under the pretext of 'reconnaissance,' Masanori's unit clashed with the Ukita Hideie army (about 17,000 men), the largest force of the Western Army.
They fell into a crisis, retreating about 500 meters under the fierce attack of the 8,000-strong vanguard led by Akashi Takenori, but the situation reversed with the arrival of reinforcements and the defection of Kobayakawa Hideaki.
Masanori achieved the military merit of driving the Ukita unit to destruction.

For this achievement, Masanori was granted Aki and Bingo provinces, totaling 498,000 koku, which were the former territories of the Western Army's commander-in-chief, Mori Terumoto.
Being given the castle of the enemy commander-in-chief was proof that Masanori was evaluated as having the 'greatest merit.'

However, this victory led to an ironic result.
After the war, Ieyasu successively confiscated or reduced the fiefs of Toyotomi-affiliated daimyo who supported the Western Army, including Mitsunari, and reduced the Toyotomi family to a mere daimyo of Owari Province.
He then became Shogun and opened the Edo Shogunate.
Masanori had fought to regain a 'Toyotomi world without Mitsunari,' but in the end, he had helped the Tokugawa usurp the Toyotomi.

4. As Lord of Hiroshima: From Warrior to Ruler

From the end of the fifth year of the Keicho era (1600) to the sixth year (1601), Masanori entered Hiroshima Castle.
Ieyasu's strategy in placing Masanori in Hiroshima, a key point in the western region, was to keep the Mori clan (in Nagato and Suo), who were also placed in the western region, in check.

The first thing Masanori did in Hiroshima was the handover process from the previous lord, the Mori clan. He demanded the return of the land tax that the Mori side had collected and taken away just before their confiscation, and forced the former Mori retainers who remained in the territory to choose between 'serving as Fukushima retainers or falling to the status of farmers.'

Then, by the autumn of the sixth year of the Keicho era, he conducted a large-scale land survey (re-measurement of land registers) in both Aki and Bingo provinces.
Based on the results of this survey, about 900 villages were established, and village officials such as village headmen (shoya) and group leaders (kumigashira) were appointed in each village under the command of the district magistrates.
The survey results were also made public to the farmers, and a 'land tax village contract system by all farmers' was realized, in which land tax was collected in accordance with actual yields.

Masanori's management of his domain was not merely military rule.
He also focused on the development of the castle town, changing the route of the Saigoku Kaido (Sanyo Road), which had passed through the north side of the castle in the Mori era, to the south side of the castle town, making it run east-west through the center of the town. As a result, merchants and travelers came and went along the road, and economic activity was incorporated into the castle town.
New towns such as 'Ebisu-cho' were established along the new road, and the basic framework of the current central Hiroshima city was formed during this period.

He also actively engaged in flood control projects.
Since Hiroshima, located on the delta of the Ota River, was exposed to the risk of constant flooding, Masanori built solid stone walls on the embankments of the main river, strengthening the defensive structure that used the river as a natural fortress while preventing floods.

He also worked energetically on the construction (expansion and renovation) of Hiroshima Castle, and from the first month of the sixth year of the Keicho era, all his retainers worked together to maintain the stone walls and the keep.
Records also remain of him inviting the 'Anoshu,' a group of experts in stone wall construction from Omi Province, to carry out the stone wall work.

Even more interesting is the organization of Shugendo (mountain ascetics).
According to the 'Jowaji Documents' discovered in recent years, Masanori placed the mountain ascetics in his domain under his control through positions such as 'Fudagashira,' and utilized them as intelligence agents who could move freely through the mountains and fields to guard the borders and gather information.
This shows the figure of a meticulous ruler, overturning the conventional image of a 'crude warrior.'

Due to this good governance, the rice yield increased from approximately 400,000 koku during the Mori era to over 510,000 koku during the Fukushima era.
Masanori was a person who possessed not only talent in 'military affairs' but also in 'civil administration'.

5. The Blunder of a Heavy Drinker: The Anecdote of the Famous Spear 'Nihongo'

An anecdote about alcohol is indispensable when talking about Fukushima Masanori.
The most famous is likely the story of the transfer of the famous spear 'Nihongo,' which became the model for the Kuroda-bushi folk song.

One New Year's, Mori Tahei (Mori Tomonobu) visited the Fukushima residence as an envoy for Kuroda Nagamasa.
A banquet to celebrate the New Year was in full swing at the Fukushima residence, and Masanori was already in a state of intoxication.
He repeatedly urged Tahei, known as a heavy drinker, to drink, but Tahei firmly refused, saying, 'As long as I am here as an envoy, I must not be rude.'

Then, Masanori began to provoke him, saying, 'Kuroda's samurai are weak drinkers.'
Tahei, whose lord and domain's honor had been insulted, drank down a large cup filled to the brim with three sho of sake in one go.
Then, accepting Masanori's promise that 'if you drink it all, you can have whatever you wish for,' he requested 'Nihongo,' one of the three great spears under heaven.

Nihongo was a prestigious spear passed down from Emperor Ogimachi to Ashikaga Yoshiaki, Oda Nobunaga, and Toyotomi Hideyoshi, and Masanori had received it from Hideyoshi for his military achievements in the Siege of Odawara (1590).
A flustered Masanori sent envoys multiple times to beg for its return, but Tahei firmly refused, stating, 'A samurai does not go back on his word.'
Nihongo never returned.

This anecdote was passed down throughout the Edo period as the folk song 'Kuroda-bushi' and remains widely known today.
Nihongo is currently housed in the Fukuoka City Museum, and the thrill of this anecdote continues to captivate people.

However, the source of this episode is primarily secondary historical materials compiled by the Kuroda family, such as the 'Kuroda Kafu' and 'Kuroda Kashinden,' and no reliable primary source recording this specific exchange at the banquet has been discovered to date in letters or diaries from the time of Masanori and Tahei.
While the spear Nihongo itself exists and its provenance is generally accepted as fact, the detailed exchange at the banquet may be a story embellished in the style of a lecture, with some kernel of truth at its core.

6. The Road to Forfeiture: The Ruin Brought by the Repair of Hiroshima Castle

In the first year of Genna (1615), when the Toyotomi family perished in the Siege of Osaka, the Tokugawa Shogunate enacted the 'Buke Shohatto' (Laws for Military Houses) as a basic law for controlling daimyo.
One of its important clauses was, 'Regarding the repair of castles in various provinces, one must always report it' (repairs to castles must be reported to the Shogunate and permission obtained).
Furthermore, under the 'One Castle per Province' law, daimyo were in principle allowed to possess only one castle per province.

The misfortune for Masanori was that a major flood occurred in the third year of Genna (1617), damaging the main keep, second bailey, third bailey, and stone walls of Hiroshima Castle.
Masanori followed the law and applied to the Shogunate for permission to repair them.

However, permission was not easily granted by the Shogunate.
The castle was the center of domain administration, and leaving it unattended would hinder not only its defensive functions but also its administrative functions.
Driven to desperation, Masanori began the minimum necessary repair work in April of the fourth year of Genna (1618).
While he perceived this as an 'emergency evacuation measure,' from the Shogunate's perspective, it appeared as if he had created a fait accompli of 'unauthorized repairs.'

In April of the fifth year of Genna (1619), Shogun Tokugawa Hidetada was enraged upon receiving this report.
Initially, he considered forfeiture, but he decided to grant a pardon on the conditions of 'demolishing all repairs except for the main keep' and 'the heir Tadakatsu coming to Kyoto.'
Masanori went to Edo to apologize and offered to demolish the repaired parts.

However, Masanori only 'demolished the repairs to the main keep' and left the repairs to the second and third baileys as they were.
Furthermore, he delayed the departure of Tadakatsu, who was supposed to be sent as a hostage, and when asked for an explanation, he showed an attitude of refusal, saying, 'Everything depends on my father.'

In June of the same year, the Shogunate ordered Masanori to forfeit his approximately 500,000 koku in Aki and Bingo, and ordered a reduced transfer to Takai District in Shinano Province (20,000 koku) and Uonuma District in Echigo Province (25,000 koku), for a total of 45,000 koku.
It was a humiliating punishment, a 91% reduction from 490,000 koku to 45,000 koku.

The retainers at Hiroshima Castle and Mihara Castle were initially prepared to hole up in the castles as the safety of their lord, who was detained in Edo, was unknown, but following Masanori's instruction to 'not cause a disturbance,' they handed over the castle grounds in an orderly manner.
This resolute response was praised by the Shogunate and has been passed down as a 'model for daimyo forfeiture'.

The superficial reason for the forfeiture was a violation of the Buke Shohatto, but there were complex factors in the true background.
First, vigilance against Toyotomi-loyalist daimyo due to their blood ties with Hideyoshi.
Second, the fact that the Shogunate did not trust Masanori, as evidenced by him not being allowed to participate in the Siege of Osaka and being kept under house arrest as a resident in Edo.
Third, the precedent of his younger brother, Fukushima Takaharu, having been forfeited on suspicion of colluding with the Toyotomi family.
Masanori's forfeiture was not a matter of individual character, but a political decision by the Tokugawa regime to systematically eliminate the Toyotomi-loyalist military faction.

7. The End in Shinano: The Quiet Final Years of a Military Commander

In October of the fifth year of Genna (1619), Masanori retired to Takaino in Shinano (present-day Takayama Village, Kamitakai District, Nagano Prefecture).
Although he fell from a great lord of 500,000 koku to a small daimyo of 40,000 koku, Masanori did not abandon his responsibilities as a lord.

Immediately after arriving, Masanori entered the priesthood, took the name 'Kosai,' and handed over the family headship to his eldest son, Fukushima Tadakatsu.
However, in September of the following year, the sixth year of Genna (1620), Tadakatsu passed away prematurely at the young age of 23.
Overcome with deep grief, Masanori returned the 25,000 koku in Uonuma District, Echigo Province, to the Shogunate.

Even during his five years in Shinano, where his holdings were reduced to a mere 20,000 koku, Masanori conducted a comprehensive land survey of his territory and promoted the development of new rice fields and flood control projects.
The 'Daifu no Senryo-zutsumi' (The Daifu's Thousand-Ryo Embankment), said to have been built to prevent the flooding of the Matsukawa River, a tributary of the Chikuma River, still remains in part as a local historical site, conveying his administrative achievements to the present day.

It is said that because of such good governance, Masanori was beloved by his subjects.
He frequently visited Gansho-in Temple in Obuse Town, where a mausoleum for Masanori Fukushima still exists today.

On July 13, 1624 (the first year of the Kanei era), Masanori passed away in Takaino.
He was 64 years old (by traditional Japanese counting) or 63 years old by modern reckoning.
The cause of death is considered to be illness, though there are also theories of ritual suicide.

The problem was that his retainer, Shirobei Tsuda, cremated the body before the shogunate's coroner, Masayoshi Hotta, arrived.
Under the laws of the time, it was mandatory for a daimyo's death to be inspected by the shogunate, and citing this procedural violation, the shogunate confiscated his remaining 20,000 koku.

In the following year, 1625, the shogunate, considering Masanori's past achievements, granted his third son, Masatoshi Fukushima, 3,112 koku to serve as a hatamoto, but the line was temporarily extinguished after Masatoshi died without an heir.
Later, Masakatsu, the grandson of Katsutada Fukushima, revived the family and served for generations in roles such as the Goshoinban (shogunal guard), but the Fukushima family as a daimyo house had completely vanished.

8. A Tragedy at the Turning Point of an Era

The life of Masanori Fukushima symbolizes the transition from the Sengoku period, where breakthroughs by military force were valued, to the Edo period, which demanded governance through law and order.

Masanori, who distinguished himself in battle at Shizugatake and Sekigahara and demonstrated his skills in land surveying, flood control, and castle town development as the lord of the Hiroshima Domain, was by no means a 'reckless warrior'.
His urban planning in Hiroshima, flood control projects, and the construction of an information network utilizing Shugendo practitioners all speak to his first-class administrative abilities.

However, at the root of his principles of action was always a Sengoku-era value system that trusted in 'one's own judgment and strength'.
'Mitsunari is a villain near the lord, so I must strike him,' 'The castle is damaged, so I must repair it,' 'My lord has died, so I must hold a funeral'—these actions were 'just' and 'rational' within the ethical framework of the Middle Ages.

Yet, in the early modern legal system constructed by the Tokugawa, these were all considered 'procedural violations' and 'rebellion'.
The world had become one where 'procedures,' such as reporting to and obtaining permission from the shogunate, took precedence over individual bravery or judgment.

The Tokugawa regime demonstrated the superiority of its system to daimyo across the country by crushing the massive 'individual military power' that was Masanori through the 'violence of the law' known as kaieki (attainder).
The removal of Masanori was a historical watershed moment, signaling that Japanese society had irreversibly shifted from 'self-help through military force' to 'public governance through law and order'.

After Masanori's attainder, Nagayoshi Asano was transferred to Hiroshima from Kii, and Yorinobu Tokugawa (the tenth son of Ieyasu) entered Wakayama, establishing the Kishu Tokugawa family.
As part of Hidetada's reorganization of daimyo placements, Masanori was excluded from the governance system of the peaceful era.

The tragedy of the warrior Masanori Fukushima was not merely personal misfortune, but part of a larger historical flow in which the era itself no longer had a need for him. From military rule to civil administration, from war to peace.
Masanori's life is the story of the glory and frustration of a single warrior standing at that turning point.

Summary

Tracing the life of Masanori Fukushima reveals that he was a multifaceted figure, different from the popular image of a 'hard-drinking, reckless warrior'.
Raised as a close aide to Hideyoshi from childhood, having achieved the honor of the first spear at Shizugatake, fighting as the vanguard of the Eastern Army at Sekigahara, and managing his domain excellently in Hiroshima, Masanori was a warrior who demonstrated talent in both military prowess and governance.

However, his tragedy lies in the fact that his talents were conversely viewed as 'risk factors' during a period of transition.
His blood ties to the Toyotomi family, his existence as a symbol of the military faction, and above all, his temperament as a Sengoku warrior who acted on 'his own judgment'.
All of these were elements that the Tokugawa shogunate, which valued law and order, had to be wary of.

The 'blunder' of unauthorized repairs to Hiroshima Castle was merely a pretext for his attainder. Looking at the subsequent actions of the Tokugawa regime, it is clear that even without that incident, Masanori would have eventually been removed for some reason.

Masanori's life is the story of a warrior tossed about by the changes of the times, and at the same time, a story that symbolizes the great historical turning point where Japan transitioned from the Middle Ages to the early modern period.
From the age of military force to the age of law. In that gap, Masanori lived as the last warrior of the Sengoku period, and then he vanished.

References

Main Reference Materials

1. "History of Hiroshima Prefecture" (Hiroshima Prefecture, 1976-1981)

2. "History of Hiroshima City" (Hiroshima City)

3. "Biography of Fukushima Masanori" by Ryutaro Tabui (1917)

4. "Tokugawa Jikki" (Compiled by the Edo Shogunate, 1809-1849)

5. "History of Nagano Prefecture" (Nagano Prefecture History Publishing Association, 1971-1992)

Web Resources

1. Hiroshima Castle Official Website: "The Entry and Attainder of the Fukushima Clan"https://hiroshimacastle.jp/history/history02/

2. Fukuoka City Museum: Materials related to "Nihongo"

3. National Diet Library Digital Collections

4. Historiographical Institute, The University of Tokyo Database

5. Japanese Historical Figures: "Fukushima Masanori"

6. Nagoya Touken World: "Tokugawa Ieyasu and the Battle of Sekigahara"

7. Touken World: "Anecdotes of Mori Tahei and the Famous Spear 'Nihongo'"

8. Koun Shrine: "The Famous Spear Nihongo"

9. Sengoku History: "The Attainder of Sengoku Daimyo and the Dawn of the Tokugawa Era"

10. Wikipedia: "Fukushima Masanori," "Nihongo (Spear)," "Seven Spears of Shizugatake"

Academic Papers

1. Jun Shiramine, "The Attack on the Seven Toyotomi Generals was a 'Litigation Dispute'," Shigaku Ronso No. 48 (Beppu University, 2018)

2. Kazuhiko Kasaya, "The Attack on Ishida Mitsunari by the Seven Toyotomi Generals," Nihon Kenkyu Vol. 22 (International Research Center for Japanese Studies, 2000)

3. Yuichiro Ando, "A Study on the Combat Duration of the Battle of Sekigahara"