was a Japanese samurai general and daimyo under the Sengoku period daimyō, and later shōgun, Tokugawa Ieyasu. He led the clan after the death of Ii Naotora. He married Tobai-in, Matsudaira Yasuchika's daughter and adopted daughter of Tokugawa Ieyasu.

Ii Naomasa joined the ranks of the Tokugawa clan in the mid-1570s, rising swiftly through the ranks and became particularly famous after the Battle of Komaki and Nagakute, as he is recognized as one of the Four Guardians of the Tokugawa along with Honda Tadakatsu, Sakakibara Yasumasa, and Sakai Tadatsugu. Ii Naomasa then eventually became the master of a sizable holding in Ōmi Province, following the Battle of Sekigahara in 1600. His family, like the Tokugawa, had originally been retainers of the Imagawa clan, but following the death of the clan's leader, Imagawa Yoshimoto, in the Battle of Okehazama (1560), confusion and general chaos ensued. Naomasa's father, Ii Naochika, was falsely convicted of treason by Yoshimoto's paranoid successor, Imagawa Ujizane, and was subsequently killed.

Naomasa, then a very small child, escaped his danger. After many difficulties, Ii Naotora succeeded the Ii clan and become the guardian of Naomasa. It was said the house of Ii clan invested greatly in Naomasa's education in preparation to entrust him to Ieyasu as a bid to save the Ii clan from crisis. which joined the Tokugawa clan's rank after Ieyasu's invasion of Totomi in 1568. As they entered service under Ieyasu, they were placed by Ieyasu under The command of Naomasa.

War against Takeda & Hōjō clan

In 1576, Naomasa fought for the first time in the battle against Takeda Katsuyori's forces at Shibahara (芝原) in Tōtōmi Province. Later Naomasa was seen alongside Ieyasu's Hatamoto vanguards, alongside Honda Tadakatsu and Sakakibara Yasumasa. At the age of 18, Naomasa participated in the Tokugawa army attack on Tanaka castle which guarded by Takeda clan general named Ichijō Nobutatsu. In this battle, Naomasa fought together with Matsudaira Ietada, Sakakibara Yasumasa, and Honda Tadakatsu as they all climbed to Tanaka castle wall and fighting Nobutatsu's soldiers.

In 1578, at the age of 18, Naomasa was given control of 10,000 koku of domain, due to unspecified distinguished military merit during that year. Later, Arthur Lindsay Sadler wrote that At the age of 19, Naomasa gained attention for his first notable performance in battle. It was said that during this period, Naomasa gained Ieyasu's favor due to his blood relation with Lady Tsukiyama, Ieyasu's legal wife. During this journey, Naomasa and other senior Ieyasu retainers such as Sakai Tadatsugu and Honda Tadakatsu fought their way through raids and harassment from Ochimusha-gari (Samurai hunter) outlaws during their march escorting Ieyasu, and sometimes advancing by usage of gold and silver bribes given to some of the more amenable Ochimusha-gari groups. As they reached Kada, an area between Kameyama town and Iga, the attacks from Ochimusha-gari finally ended as they reached the territory of Kōka ikki Jizamurai warriors who were friendly to the Tokugawa clan. The Koka ikki warriors then escorted the group while assisting them by eliminating the threats of the Ochimusha-gari outlaws until they reached Iga Province, where they were further protected by samurai clans from Iga ikki which then accompanied the Ieyasu group until they safely reached Mikawa.

After Ieyasu's return to Mikawa, Tenshō-Jingo War broke out between the Tokugawa clan and Hōjō clan in a contest to gain control the area of Shinano Province, Ueno region, and Kai Province Kai Province (currently Gunma Prefecture), which had been vacant since the destruction of Takeda clan and the death of Oda Nobunaga. Ieyasu lead an army of 8,000 soldiers entering Kai, Shinano Province, and Ueno, to annex it. However, the Hōjō clan in the Kantō region also led an army of 55,000 men and crossed the Usui Pass to invade Shinano Province. In the battle of Wakamiko, 8,000 Tokugawa soldiers fought against around 50,000 soldiers of Hojo soldiers led by Hōjō Ujinao. Ii Naomasa was recorded as participating in these engagements. In the middle of this conflict, Naomasa further managed to recruit more samurais that had formerly served various Takeda generals such as Ichijō Nobutatsu, Yamagata Masakage, Masatsune Tsuchiya, and Hara Masatane with the help of former Takeda clan retainer named Kimata Morikatsu who organized the contacts of those samurais with Naomasa. Aside from military service, Naomasa played diplomatic role during this conflict as he received around 41 letters from many former Takeda clan's vassals to submit to Ieyasu. In total, more than 800 vassals of Takeda clan from Kofu Province recruited by Ieyasu during the fight against the Hōjō which lasted for 80 days. In the final phase of this conflict, Naomasa participated in the battle of Kurokoma, where the smaller Tokugawa army managed to defeat the much larger Hōjō armies, despite being reinforced by 10,000 soldiers by Satomi clan from Awa Province (Chiba). From November to January of the following year, Naomasa worked together with another Tokugawa general Torii Mototada, and two former Takeda clan generals who now joined Tokugawa clan's rank, Hoshina Masanao and Suwa Yoritada, to attack Chikuma District which was controlled by a Hōjō clan vassal named Ogasawara Sadayoshi. By February 10, Sadayoshi surrendered and joined the Tokugawa side. The result of this war, combined with the defection of Sanada Masayuki to the Tokugawa side has forced the Hōjō clan to negotiate truce with Ieyasu. The Hōjō clan then sent Hōjō Ujinobu as its representative, while the Tokugawa sent Naomasa as its representative to negotiate the peace conditions.

According to the Meishō genkō-roku record, after the conflict with the Hōjō clan, Ieyasu organized a kishōmon(blood oath) with many samurai clans that formerly were vassals of the Takeda clan assigned under the command of Tokugawa clan retainers. Ieyasu Tokugawa planned to subduct the largest portions of former Takeda samurai under Naomasa's command, having consulted and reached agreement with Sakai Tadatsugu, a senior Tokugawa clan vassal. However, Ieyasu's decision garnered protest from Sakakibara Yasumasa, who went so far as to threaten Naomasa. Tadatsugu immediately defended the decision of Ieyasu in response and warned Yasumasa that if he did any harm to Naomasa, Tadatsugu would personally slaughter the Sakakibara clan; thus, Yasumasa heeded Tadatsugu and did not protest further. Then Ieyasu decided assigned 70 members of former Takeda samurais from Tsuchiya clan under the command of Ii Naomasa. During this year, Naomasa was also given an increase of his domain to 40,000 koku. Motosuke Ikeda was also killed by Andō Naotsugu. Meanwhile Ikeda Terumasa retreated from the battlefield. Eventually, the Tsuneoki and Mori forces were crushed, and the battle ended in victory for the Tokugawa force. In this battle, Naomasa fought so valiantly that it elicited praise from Toyotomi Hideyoshi, who was on the opposing side.

After the Battle of Komaki and Nagakute, the front line in northern Owari reached a stalemate. Ieyasu and Oda Nobukatsu led 20,000 soldiers and besieged three castles: Kanie Castle, Maeda Castle, and Shimoichiba Castle. The Kanie castle was defended by Maeda Nagatane and Takigawa Kazumasu. Tadatsugu, Okanabe Mori, and Yamaguchi Shigemasa spearheaded the attack towards Shimoichiba castle. On June 22, Nobukatsu and Ieyasu launched an all-out attack on Kanie Castle. The soldiers were led by Tadatsugu, While Naomasa, Ishikawa Kazumasa, Honda Tadakatsu, Sakakibara Yasumasa, and Matsudaira Ietada were deployed in reserve before entering the battle with Ieyasu himself. On June 23, Ieyasu entered the castle with Sakakibara Yasumasa, thus the castle was subdued.

150px|right|thumb|Osuga Yasutaka, senior Tokugawa general

In 1585, during the Tokugawa clan's first siege of Ueda Castle against Sanada Masayuki, Ii Naomasa led 5,000 soldiers along with Osuga Yasutaka and Matsudaira Yasushige led reinforcements to cover the retreat of Tokugawa forces after they failed to pacify the castle due to hostile movements from Uesugi Kagekatsu. In the same year, Ishikawa Kazumasa, a senior vassal of Tokugawa, defected from Ieyasu to Hideyoshi. This incident caused Ieyasu to undertake a massive reform of the structures of the Tokugawa clan's military government. At first, Ieyasu ordered Torii Mototada, who served as the county magistrate of Kai, to collect military laws, weapons, and military equipment from the time of Takeda Shingen and bring them to Hamamatsu Castle (Hamamatsu City, Shizuoka Prefecture). Later, he also appointed two former Takeda vassals, Naruse Masakazu and Okabe Masatsuna, as magistrates under authority of Ii Naomasa and Honda Tadakatsu, while he also ordered all of former Takeda vassals who now serve him to impart any military doctrines and structures they knew during their service under Takeda clan, and lastly, he ordered the three of his prime generals, the so-called "Tokugawa Four Heavenly Kings," Ii Naomasa, Honda Tadakatsu, and Sakakibara Yasumasa, to serve as supreme commander of this new military regiments.

In 1586, according to "Sakakibara clan historical records", Ieyasu sent Naomasa, Honda Tadakatsu, and Sakakibara Yasumasa as representatives to Kyoto, where the three of them were regarded as "Tokugawa Sanketsu"(Three great nobles of Tokugawa). Then in following month, the three of them were joined by Sakai Tadatsugu to accompany Ieyasu in his personal trip to Kyoto, where the four of them "became famous". On September 29, Naomasa and Honda Tadakatsu led their army to rendezvous with Ikeda Terumasa's army, where they engaged Oda Hidenobu army in the Battle of Gifu Castle. In this battle, Hidenobu's castle was deprived of the expected support from Ishikawa Sadakiyo (石川貞清), who decided to not help the Western army in this war after he made an agreement with Naomasa. Hidenobu was prepared to commit seppuku, but was persuaded by Ikeda Terumasa and others to surrender to the eastern forces, and the Gifu Castle fell.

thumb|250px|right|Site of [[Matsudaira Tadayoshi and Ii Naomasa's Positions in the Sekigahara battle.]]

On October 21, in the Battle of Sekigahara, Naomasa gave a notable performance where his unit outpaced those of other generals such as Fukushima Masanori, drawing the "first blood", where Naomasa led 30 spearmen from the center of the formation and charged the ranks of the western army, and then he was followed by Masanori whose units started clashing against Ukita Hideie units. However, some modern historians now view Naomasa's actions as a result of confusion on both sides as there was heavy fog covering the battlefield, and this may have caused him to unintentionally start the first clash against the enemy, which broke Ieyasu's previous order to let Masanori perform the first move of the battle. Meanwhile, Professor Watanabe Daimon offered an explanation that by many indications according to the battle records, the assignment of Naomasa as Ichiban-yari or the first unit to charge the enemy were already settled before the battle, where Masanori had agreed with Naomasa's intention to lead the first attack. Daimon argued that as Naomasa was appointed by Ieyasu supreme field commander, Naomasa was responsible for all commands and strategies during the clash in Sekigahara. As the battle entered its final phase, Naomasa turned his attention towards the Shimazu troops.

After the Sekigahara battle, Naomasa sought pardons with Ieyasu for Sanada Masayuki and Sanada Yukimura at the behest of Sanada Nobuyuki. Naomasa also had his fief increased from 60,000 koku into 180,000 koku. Naomasa complained of this to Nagai Naokatsu, as he considered it small when compared to Ikeda Terumasa who received 520,000 Koku.

250px|right|thumb|Hikone castle which under control of Ii clan since Ii Naomasa

After defeating the Western Army at Sekigahara, Ieyasu dispatched his army to attack Sawayama Castle in Ōmi Province, the former territory of Ishida Mitsunari with Kobayakawa Hideaki's troops at the vanguard. Most of the castle's troops were at the Battle of Sekigahara, leaving the castle's garrison at 2,800 men. Despite the absence of the lord of the castle, the castle's soldiers fought well, but eventually some soldiers such as Moritmo Hasegawa betrayed the castle and opened the castle for the besieging army. most of Mitsunari relatives, including his father Masatsugu, Masazumi, and Kagetsuin (Mitsunari's wife), were killed in battle or committed suicide. After the castle fell in 1601, Naomasa was appointed to take control of Sawayama Castle, However, as the castle was viewed as unstrategic in location, Naomasa ordered the castle building along with its structures dismantled, while transferring its materials instead to Kohei castle, another castle which was controlled by Naomasa. He also was appointed to the rank of Junior Fourth Rank.

Several months after the battle in Sekigahara, Naomasa sent military reinforcements to assist Yamauchi Kazutoyo in pacifying the rebellion in Tosa Domain against retainers of Chōsokabe clan, and the Ichiryo Gusoku peasant army. The wound which was suffered by Naomasa at Sekigahara prevented his personal involvement in the quelling of the last vestiges of the anti-Tokugawa faction. The 273 dead rebels heads were decapitated and sent to Ii Naomasa.

Death

Ii Naomasa's premature death in 1602 has been widely blamed on the wound he received at Sekigahara. Naomasa was highly regarded by Tokugawa Ieyasu, so it is no surprise that his sons Naotsugu and Naotaka succeeded him in his service and title. However, Naotsugu managed to anger Ieyasu by refusing to take part in his campaign to reduce the Toyotomi clan stronghold at Osaka.

In 1917, Naomasa was posthumously granted the courtesy title of junior third rank (ju san-mi, 従三位) by Emperor Taishō.

Personality

thumb|Ii Naomasa Armor at [[Hikone Castle]]

According to the Confucian scholar Oze Hoan [ja] (1564–1640), in his biographical work Taikōki, Ii Naomasa had a beautiful face (Bishōnen), which impressed the mother of Toyotomi Hideyoshi, Ōmandokoro, during Naomasa's stay in Kyoto. The "Clan records" chronicles from Edo period also stated that during the battle of Komaki-Nagakute, Naomasa were described as "handsome and has small physical stature". However, despite his unintimidating built, Naomasa fought ferociously in the Battlefield and wearing distinguishable red armor and helmet with long horns, which rendered him a nickname 'Aka-oni'(red demon).

Naomasa was known as a brutal disciplinarian with violent temper, and punished his subordinates for the slightest mistakes, earning him the nickname of Hitokiri Hyōbu(Hyōbu the Manslayer/mass-murdering minister). According to Meishō genkō-roku (A record of famous commanders' words), Naomasa's strict attitude were influenced by Ōkubo Tadayo, who once advised Naomasa to not expect any luxurious meal during war.

An anecdote from Sakakibara clan historical records has stated that among Ieyasu generals, Honda Tadakatsu excelled in bravery and Sakakibara Yasumasa excelled in leadership, while Ii Naomasa possessed both qualities. However, modern historian Hiroyuki Kikuchi does not agree with the traditional assessment and questioned leadership quality of Naomasa, as Kikuchi quoted the historical research works of Noda Hiroko, which titled "Ii Naomasa", that during the battle in Komaki-Nagakute, Naomasa acted recklessly by personally going to fight on the frontline, engaging in melee and grappling enemy soldiers, thereby exposing himself in dangerous position. This prompted his own subordinate, Andō Naotsugu, to chastise Naomasa for his recklessness and not behaving like a military commander who should have focused on giving commands to his soldiers from the rear. Furthermore, Kikuchi pointed out the action of Naomasa in Nagakute also gave much trouble for his other field officer, Kimata Morikatsu, in coordinating their troops. Kikuchi argued that instead of Naomasa, it was Naomasa subordinates, the former Takeda clan "Red Guard" troops. who really built up their reputation as a fearsome military unit.

Naomasa was also known for his political astuteness, which enabled him to command respect when he was tasked to lead the garrison of Minowa Castle.

Family

In 1590, Tobai-in gave birth to Ii Naokatsu. However, in the same year, Naomasa's second son, Ii Naotaka, was born. Naotaka's mother, Ako, was said to be the daughter of Inbu Tokuemon, who served Matsudaira Yasuchika. When Naomasa was married to Tobai-in, Ako came to the Ii family as a maid to serve as maid. It was said that Naomasa was afraid of his wife and hid not only Ako but also Naotaka. Naomasa was afraid of his wife. According to one theory, Ako risked her life to have her son Naotaka acknowledged as her son. After going to such lengths, even Naomasa had no choice but to acknowledge Naotaka as his own son.

Naomasa had built up close relations with the Matsudaira clan through marriages, as his wife, Hana, was a daughter Matsudaira Yasuchika. Yasuchika was originally from the Matsui clan and was a senior vassal and guardian of the Tojo branch of Matsudaira clan. The Tojo Matsudaira eventually lost their heir, but Tokugawa Ieyasu had his fourth son, Matsudaira Tadayoshi, to inherit the position of the head of Tojo Matsudaira. Furthermore, Tadayoshi married Masako, the daughter of Naomasa and Hana. Historian Toshikazu Komiyama believed this steps were an effort of Ieyasu to strengthen and rejuvenate the Ii clan after facing danger of extinction due to decades of troubles which weakened them internally.

thumb|The monument of Ii Naomasa at Ryōtan-ji in Hamamatsu, Shizuoka

Ii Naomasa was also known as the founder of Hikone Castle, after he given task by Tokugawa Ieyasu appoint him the rule of a new domain centered at Sawayama Castle. The Hikone Castle completed by his son Ii Naokatsu in 1622. The area remained under the control of Hikone Domain through the end of the Edo Period. He also known as the first governor of the newly established Hikone Domain, which formed from the eastern part of Ōmi Province that formerly known as Sawayama domain which ruled by Ishida Mitsunari.

Aside from the Hikone Domain, another historical Domain founded under Naomasa's rule were Takasaki Domain, which he control for sometimes before it was transferred to Sakai Ietsugu, son of Sakai Tadatsugu.

Naomasa's sets of armour are all preserved and exhibited within Hikone Castle museum, including an armor with golden horns in its helmet. The armor is fully coated in shu-urushi (red lacquer). This kind of armor were recorded being used by Naomasa during the battle of Komaki-Nagakute.

Ii clan's Red Demons brigade

thumb|right|Edo period depiction of the "Red Guards" (Akazonae) of the Ii clan

Ii Naomasa was known for his notable elite troops which were nicknamed as Ii clan's (Akaoni), or (akazonae).

In March 1582, the Ii clan under Naomasa absorbed many of the Takeda's samurai vassals into their ranks, after he made a blood pact (Kishômon) with 70 samurai warriors from Tsuchiya clan that formerly served Tsuchiya Masatsugu, one of Twenty-Four Generals of Takeda Shingen, to serve him as Hatamoto retainers. The negotiation to convince them to join Naomasa was aided by a former Takeda clan retainer named Kimata Morikatsu, who organized the contacts of those samurai clans with Naomasa.

Recently in 2023, a letter of Naomasa Ii's which was sent to a former Takeda general named Obata Nobusada (小幡信真) during the conflict between Tokugawa against Hojo clan, was disclosed by Hiroko Noda, an official of Hikone castle museum. The content of the letter was Naomasa's assurance to Nobusada that he would accept his surrender to Tokugawa.

The warriors which Naomasa commanded on the battlefield were notable for being outfitted almost completely in blood-red armour from their mounted samurai, bannermen, to even ashigaru. It was said this was for psychological impact, a tactic he adopted from Yamagata Masakage, one of Takeda Shingen's generals. According to Kōyō Gunkan, Obata Nobusada. who submitted to Naomasa during the Tensho Jingo war, also allegedly commanded a Red armored cavalry units which was different from the Red cavalry units of Yamagata Masakage.

Aside from the Takeda clan's samurais, Ieyasu also assigned his own vassals from Iinoya domain such as the "Iinoya's trio" (Iinoya-Sanninshu) clans to his command. One of the Iinoya's trio sons, Kondō Hideyo from the Kondō clan also entered service of Naomasa in 1584 as his Yoriki (officer) with semi-autonomous authority. Before serving Naomasa, Hideyo himself was already a veteran warrior who participated in Ieyasu's campaigns and gained many military merits in the Battle of Anegawa, Battle of Mikatagahara, Battle of Nagashino, and the Siege of Takatenjin Castle. Hideyo later also fought under Ii Naomasa's banner on the battle of Komaki-Nagakute, first siege of Ueda, Siege of Odawara, and Toyotomi's "Ōshū shioki" campaign in suppressing Kunohe Masazane's rebellion.

Furthermore, Ii Naomasa also employed Iga ninja clans from Iga Province which led by Miura Yo'emon. Miura Yo'emon was reportedly entered the service of Ii clan in 1603. This ninja army saw action during the Siege of Osaka under the lead of Ii Naotaka, heir of Naomasa who was also given control of Ii clan's red demons after Naomasa died.

Historians such as Michifumi Isoda opined that one factor in why the Tokugawa clan could conquer Japan was due to the incorporation of the former Takeda clan's vassals into its ranks, including Yamagata Masakage's elite red brigade cavalry entering into Naomasa's command.

In theater and other contemporary works, Naomasa is often characterized as the opposite of Ieyasu's other great general: Honda Tadakatsu. While both were fierce warriors of the Tokugawa, an anecdote recorded by Japanese writer Yoshiaki Kusudo states that where despite being lightly armored, Tadakatsu never received any injury during his life, while Naomasa always received wounds every battle despite heavily armored. It was said that the armor Naomasa wore reached 60 kg in weight.

A Japanese historical drama NHK show has Rihito Itagaki portray Ii Naomasa. In this show, He is depicted as playboy and handsome young vassal of Ieyasu who has an arrogant personality.

Appendix

Footnotes

References

Bibliography

  • Included in Komiyama Toshikazu『譜代大名の創出と幕藩体制』（吉川弘文館、2015年） ISBN 978-4-642-03468-5 / "Creation of Fudai Daimyo and Shogunate System" (Yoshikawa Kobunkan, 2015)

Primary sources

  • Taikōki record by Oze Hoan
  • Kansei chōshū sho kafu by Hotta Masaatsu
  • "Ii Naomasa's letters" preserved by Hikone castle
  • Tokugawa Nikki (Diary of Tokugawa)
  • "Ii clan's records" by Ii clan descendants
  • Mikawa Monogatari by Ōkubo Tadachika
  • "Kōyō Gunkan" by Kōsaka Masanobu and Obata Kagenori
  • "Sakakibara clan's records" by Sakakibara clan descendants
  • Han-Kanfu (Domain records)
  • Mikawa Go-fudoki by Hiraiwa Chikayoshi / Hosoi Ujinori.
  • Reference:
  • "Kansei Shoshu Shokafu Volume 4" National Diet Library Digital Collections
  • "Tokugawa Jitsuki Volume 1" National Diet Library Digital Collection
  • Ii family information (in Japanese)
  • Painting and brief bio of Naomasa (in Japanese)
  • Information on Naomasa, including images of his flag, battle standard, and armor (in Japanese)

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