Lifespan: Tenbun 16 (1547) to 4/7 of Keichō 16 (1611)
Titles: Junior Fifth Rank (Lower), Junior Assistant Head of the Board of Censors, Junior Fourth Rank, Chamberlain, Junior Third Rank (honorary)
Clan: Yasui → Asano
Lord: Oda Nobunaga → Toyotomi Hideyoshi → Toyotomi Hideyori → Tokugawa Ieyasu → Tokugawa Hidetada
Father: Yasui Shigetsugu
Mother: Daughter of Asano Nagatoshi
Adoptive Father: Asano Nagakatsu
Adoptive Mother: Nanamagari-dono
Wife: [Formal] Daughter of Asano Nagakatsu (Yaya, known as Chōseiin)
Children: Yoshinaga, Nagaakira, Nagashige, daughter (formal wife of Sugihara Nagafusa), daughter (formal wife of Hori Chikayoshi (Yōbaiin)), daughter (formal wife of Matsudaira Sadatsuna), daughter (wife of Tarao Mitsusada)
Asano Nagamasa served as a daimyō and the fourteenth head of the Asano clan. Nagamasa is distinguished for having served all three of the dominant lords in the Sengoku period – Oda Nobunaga, Toyotomi Hideyoshi, and Tokugawa Ieyasu. He served as the head of the gobugyō, or the Five Commissioners, who managed the system of governance during the reign of Toyotomi Hideyoshi. In the Edo period, Nagamasa served as the first head of the Makabe domain in Hitachi Province. Nagamasa was also known for his original name of Nagayoshi.
From successor to the clan to serving the Oda
Nagayoshi was born in Miyaushiro Castle located in Kitano in the Kasugai District of Owari Province. His father was Yasui Shigetsugu, lord of the castle. Asano Nagakatsu, an uncle of Oda Nobunaga and member of the archery unit, did not have a son so Nagayoshi wed his daughter, Yaya, and became an adopted son-in-law of Nagakatsu. He later succeeded Nagakatsu as head of the Asano clan. Nagakatsu’s adopted daughter, Nene (Kōdai-in) wed Toyotomi Hideyoshi so that Nagayoshi became a close relative of Hideyoshi, and, upon orders of Nobunaga, served as a yoriki, or security official for Hideyoshi. In 1573, Nagayoshi participated in an attack against Azai Nagamasa, and after Hideyoshi became lord of Odani Castle in the Azai District of Ōmi Province, was awarded a small fief of 120 koku in Ōmi.
Service as a retainer of Toyotomi Hideyoshi
After the demise of Nobunaga, Nagayoshi served Hideyoshi. For his contributions at the Battle of Shizugatake, Hideyoshi granted Nagayoshi a fief of 20,000 koku in Ōtsu in Ōmi. In 1584, he became a bugyō, or commissioner in Kyōto, later becoming the leader of the gobugyō. Hideyoshi leveraged Nagayoshi’s administrative prowess by engaging him to conduct a nationwide land survey known as the taikō kenchi. He had close relationships with daimyō in the eastern provinces, and was ordered to manage gold and silver mines that Hideyoshi’s administration had seized from various daimyō. In 1586, Nagayoshi traveled to Hamamatsu Castle after Hideyoshi’s younger sister, Asahi-hime, became the formal wife of Tokugawa Ieyasu.
In 1587, Nagayoshi took part in the pacification of Kyūshū, and became a daimyō with a fief of 80,000 koku in the village of Obama in Wakasa Province. In 1588, he was awarded the Court title of Junior Assistant Head of the Board of Censors in the Junior Fifth Rank (Lower). He participated in the Siege of Oshi Castle during the pacification of the Kantō. Nagamasa replaced Ishida Mitsunari toward the end of the campaign and to manage post-battle affairs. In 1590, Nagamasa performed a central role in the Oushū Retribution (Oushū shioki), the imposition of control over Mutsu and Dewa provinces in the Tōsan Region. Nagamasa strengthened his ties as a mediator with Nanbu Nobunao, a sengoku daimyō in Mutsu Province. He also aided in the response to riots by former retainers of the Kasai and Ōsaki clans after their removal from power by Hideyoshi. The retainers opposed the new lords – Kimura Yoshikiyo and his son, Kiyohisa. Nagamasa responded to an event known as the Revolt of Kunohe Masazane, led by an influential figure in the Nanbu clan against Nanbu Nobunao and the Oushū Retribution led by the Toyotomi administration.
In 1592, Nagamasa was bestowed the Toyotomi name. In 1593, he performed meritoriously in the campaign to invade the Korean Peninsula. This conflict, known as the Bunroku-Keichō Expedition occurred in two periods, from 1592 to 1593, and from 1597 to 1598, with the army withdrawing after the death of Toyotomi Hideyoshi. In 1593, Nagamasa was granted a fief of 215,000 koku in Fuchū and entered Kōfu Castle in Kai Province. This territory reverted to the Toyotomi administration after the death from illness of one of Hideyoshi’s senior retainers named Katō Mitsuyasu. Nagamasa was ordered to serve as a go-between with the daimyō in the eastern provinces, and engaged figures including Nanbu Nobunao, Utsunomiya Kunitsuna, Nasu Sukeharu, and Narita Ujinaga as yoriki, or security officials. Meanwhile, Date Masamune expressed dissatisfaction with the duties and dispatched a letter of separation to Nagamasa.
Late in 1597, Hideyoshi unexpectedly ordered Utsunomiya Kunitsuna removed from his role. This may have owed to discrediting by Nagamasa, who was in a position of influence as the head of the gobugyō in service to Hideyoshi. Kunitsuna did not have an heir, so he attempted to adopt Nagamasa’s third son, Asano Nagashige. Kunitsuna’s younger brother, Haga Takatake, fiercely opposed the plan. He cornered Imaizumi Takamitsu, a close associate of Kunitsuna who had been facilitating the adoption, whereupon Takamitsu took his own life. Nagamasa resented the act, and Kunitsuna may have been dismissed on the basis of Nagamasa’s response. A letter from Satake Yoshinobu to his father, Satake Yoshishige, corroborates this account. Yoshinobu was the nineteenth lineal head of the Satake clan of Dewa Province. Orders were for the removal of the Utsunomiya clan as a daimyō and yoriki, and for the Satake clan who were related through marriage. Ishida Mitsunari served as mediator in an effort to obtain exemptions from the orders. Lineal retainers such as the Haga clan who held sway over the Utusnomiya remained opposed to the ambitions of Kunitsuna and associates including the Imaizumi within the clan. Thereafter, official messengers to the daimyō in the Tōhoku and Kantō regions were chosen by, among others, Tokugawa Ieyasu, Maeda Toshiie, Gamō Ujisato, Uesugi Kagekatsu, and Ishida Mitsunari.
Nagamasa confronted numerous challenges in the Kansai Region, and had his eldest son, Asano Yoshinaga, govern Kai Province. According to a system known as kusuji-niryō, Yoshinaga assigned three administrators to each of nine districts and family members (Asano Ujishige and Asano Tadayoshi) to each of two larger territories. Under his governance of Kai, Yoshinaga also implemented Hideyoshi’s land survey and managed the reconstruction of Kōfu Castle.
Nagamasa maintained close relations with Tokugawa Ieyasu, the head of Hideyoshi’s gotairō, or Five Elders. Following Hideyoshi’s death, Nagamasa appeared to have strained relations with Ishida Mitsunari. In a letter from Satake Yoshinobu to his father, Yoshishige, he noted that Mitsunari said Nagamasa’s actions showed signs of betrayal. In 1599, Ieyasu confined Nagamasa and Maeda Toshinaga to house arrest upon suspicion of plotting an assassination, whereupon Nagamasa assigned his role as head of the clan to Yoshinaga and retired to Fuchū in Musashi Province.
The Battle of Sekigahara
In 1600, at the Battle of Sekigahara, Nagamasa provided support to Ieyasu, joining the army under the command of Ieyasu’s third son, Tokugawa Hidetada, and advancing into the Nakasen region. Yoshinaga led the eastern army to attack and capture Gifu Castle, and participated in the main battle. Afterwards, Yoshinaga was assigned to Wakayama in Kii Province and awarded a fief of 370,000 koku. Meanwhile, after formation of the Tokugawa bakufu, Nagamasa continued to support Ieyasu and, in 1605, moved to Edo. The next year, Nagamasa received a fief of 50,000 koku in Makabe in Hitachi Province for his retirement years. Nagamasa died in the area of Jinya in Makabe, and his third son, Asano Nagashige, inherited his fief.