Eishō was an era from 2/30 of 1504 to 8/23 of 1521 (based on the Japanese lunisolar calendar) in the Sengoku period.
The change from the prior era known as Bunki was related to the sexagenary cycle, also known as the Stems-and-Branches or ganzhi, a cycle of sixty terms used for reckoning time in China and the rest of the East Asian cultural sphere that appeared as a means of recording days in the first Chinese written texts. The fifty-ninth year of the cycle was theorized to represent a period of political disturbances, known as the kasshi-kakumei. To prevent this from occurring, the authorities changed the name of the era.
During this era, Gokashiwabara was the emperor; Ashikaga Yoshiki (later known as Yoshitane) (1490-1495 and 1508-1522) and Ashikaga Yoshizumi (1495-1508) served respectively as the tenth and eleventh shōgun of the Muromachi bakufu.
Key events and battles
- At the Battle of Tachikawa-no-hara, Uesugi Tomoyoshi of the Ōgigayatsu-Uesugi clan defeated Uesugi Akisada of the Yamauchi-Uesugi clan.
- Suganuma Sadanori built Noda Castle in the Shitara District of Mikawa.
- Makino Kohaku built Yoshida Castle on the northern end of the Atsumi District of Mikawa. This intensified conflict between the Makino and Toda clans while Yoshida Castle sat in a contested area.
- A confrontation arose between Ashikaga Masauji and his son, Ashikaga Takamoto. Masauji served as the second Koga kubō or head of the Kantō-Ashikaga clan based in Koga in Shimōsa Province in a lineage that continued for 130 years. The Sano clan, the Shirakawa-Yūki clan, Oyama Shigenaga, Satake Yoshikiyo, and Iwaki Yoshitaka led the support for Masauji, while Utsunomiya Shigetsuna, Yūki Masatomo, and Oda Masaharu backed Takamoto, giving rise to a succession of battles across Kantō, summarily referred to as the Eishō Conflict (Eishō no ran).
- Hōjō Sōun conducted surveys in Sagami Province.
- Yoshida Castle was toppled during which its lord, Makino Kohaku, died.
- Hosokawa Masamoto, the kanrei, or deputy shōgun, was assassinated in his residence in a plot led by one of his adopted sons, Hosokawa Sumiyuki in the Lord Hosokawa Incident (Hosokawa-dono no hen).
- Hosokawa Sumimoto joined with Miyoshi Yukinaga to kill Hosokawa Sumiyuki as retribution for the assassination of Masamoto, forcibly acquiring control of the Hosokawa-Keichō family.
- A succession struggle between Hosokawa Sumimoto and Hosokawa Takakuni known as the Eishō Disturbance (Eishō no sakuran) persisted for twenty-six years. Meanwhile, the formerly deposed Ashikaga Yoshiki allied with Ōuchi Yoshioki in a bid to regain his position as shōgun of the Muromachi bakufu.
- Nagao Tamekage, the deputy military governor of Echigo Province, supported Uesugi Sadazane to launch a sudden attack against Uesugi Fusayoshi, whereupon Fusayoshi attempted to flee to the Kantō Region with the assistance of Uesugi Akisada (the deputy shōgun of Kantō) but was cornered and killed himself at the Amamizu Pass in Echigo Province.
- Ōuchi Yoshioki reached a settlement with Shōni Sukemoto through the mediation of Ashikaga Yoshiki.
- Hosokawa Takakuni aimed to converge with the allied forces of Ashikaga Yoshiki and Ōuchi Yoshioki to oppose Hosokawa Sumimoto, and absconded from Kyōto. Ashikaga Yoshizumi (the shōgun) and supporters of Sumimoto had misgivings about a confrontation with the Ōuchi army marching toward Kyōto and retreated to the Koga District of Ōmi Province.
- Ashikaga Yoshiki returned to Kyōto and was reappointed as shōgun, while Takakuni became the kanrei, or deputy shōgun and Ōuchi Yoshioki the vice-deputy shōgun. Later, Yoshiki changed his name to Yoshitane. Takakuni was recognized as the head of the Hosokawa-Keichō family which role had earlier been forcibly taken by Sumimoto.
- Nagashino Castle was built in the Shitara District of Mikawa.
- Utsunomiya Shigetsuna defeated the Ashina clan at the Battle of Katakaku-Ikusagaya, advancing to Shiobara.
- At the Battle of Nyoigatake, the combined forces of Hosokawa Takakuni and Ōuchi Yoshioki defeated the army of Hosokawa Sumimoto.
- A major earthquake occurred in Settsu and Kawachi provinces, destroying the stone archway to the Shitenō Temple and the Fujii Temple.
- A tsunami hit Tōtōmi Province, causing a cleavage connecting Lake Hamana to the ocean.
- Ashikaga Yoshizumi died without having realized his aim to regain his position as shōgun.
- The Battle of Funaokayama occurred. Fearing an attack on Kyōto by Hosokawa Masakata, a supporter of Hosokawa Sumimoto, Ashikaga Yoshitane (the shōgun) fled to Tanba Province. With the support of Ōuchi Yoshioki, the bakufu army under Yoshitane defeated forces under Masakata camped at Funaokayama, and re-entered Kyōto. Sumimoto ran away to Awa Province in Shikoku.
- A dispute arose within the family of the Koga kubō, the branch of the Ashikaga family ruling the Kantō from their base in Koga in Shimōsa Province. Utsunomiya Shigetsuna supported Ashikaga Takamoto, the son-in-law of Ashikaga Masauji (the second Koga kubō) in opposition to a senior retainer of Masauji named Haga Takakatsu. After Shigetsuna was made to retire through the scheming of Takakatsu, Shigetsuna sought to bring the fractured clan under control by killing Takakatsu and summarily attacking the castle residence of the senior retainers associated with the Haga clan. This escalated into a major internal conflict known as the Utsunomiya Disturbance (Utsunomiya no sakuran). Shigetsuna finally quelled the disturbance after two years of conflict, reconstituted the retainers, and took control of the clan.
- A major tsunami hit Awa Province. Many residences along Shishikui Bay were washed away.
- Hōjō Sōun built Tamanawa Castle in the Kamakura District of Sagami Province.
- Yamana Toyoshige, the military governor of Inaba Province, was killed by his younger brother, Yamana Toyoyori, in Fuse-tenjinyama Castle in the Takakusa District of Inaba Province, an event known as the 申の歳崩れ.
- Anayama Nobutō, the landowner of Kawachi in Kai Province, was assassinated by his eldest son, Anayama Seigorō.
- At the Battle of Takebayashi, an allied army of 20,000 soldiers led by Satake Yoshikiyo, Iwaki Yoshitaka, and members of the Nasu clan took aim at the Utsunomiya clan from Shimotsuke Province who were exhausted from the Utsunomiya Disturbance. Utsunomiya Tadatsuna, along with reinforcements led by Utsunomiya Shigetsuna and Yūki Masatomo, repelled the attack. This victory provided a significant boost to Ashikaga Masauji, the second Koga kubō, or shōgun of the Kantō, as well as fuel the rise of the Shimotsuke-Utsunomiya clan.
- Utsunomiya Shigetsuna defeated a large army of the Satake clan led by Satake Yoshikiyo at the Battle of Nawazuri in Shimotsuke Province, dealing a major blow to the Satake clan.
- Ōuchi Yoshioki, the vice-deputy shōgun, departed from Kyōto and returned to his home base in Yamaguchi in Suō Province.
- Hosokawa Sumimoto raised arms again from Awa Province with the aim of toppling Hosokawa Takakuni. He stationed forces in Settsu Province under the direction of Miyoshi Yukinaga.
- Hosokawa Takakuni lost to his arch-enemy, Hosokawa Sumimoto, and retreated to Sakamoto in Ōmi Province.
- A major earthquake struck Kumano on the end of the Kii Peninsula. Shrines and temples in Nachi and Kumano were damaged and homes washed away in a tsunami.
- The army of Hosokawa Takakuni, with the support of the Asakura, Toki, and Rokkaku clans, launched a counter-attack in Kyōto at the Battle of Tōjiin. Hosokawa Sumimoto lost and withdrew to Settsu Province, while Miyoshi Yukinaga killed himself.
- Hosokawa Sumimoto died at Shōzui Castle in Awa Province, leading to a temporary quieting down of the conflict with Hosokawa Takakuni.
- Ashikaga Yoshitane, the shōgun, fled Kyōto owing to deepening differences with Hosokawa Takakuni.
- The enthronement ceremony was held for Emperor Gokashiwabara. After twenty-one years, a ceremony was finally held for his accession to the throne.
- Ashikaga Kameōmaru, an orphan of Ashikaga Yoshizumi who was protected by Uragami Muramune (the deputy military governor of Bizen Province), was received by Hosokawa Takakuni and marched into Kyōto.
- Hatakeyama Tanenaga, military governor of Kii Province
- Chōsokabe Kunichika, sengoku daimyō of Tosa Province
- Kikuchi Yoshitake, sengoku daimyō of Higo Province and uncle of Ōtomo Yoshishige
- Kujō Tanemichi, kanpaku, or chief councilor to the emperor
- Yamashina Tokitsugu, kugyō, or senior official of state affairs
- Ōuchi Yoshitaka, sengoku daimyō of Suō and Nagato provinces; son of Ōuchi Yoshioki
- Kamiizumi Nobutsuna, military strategist in Kōzuke Province
- Ashikaga Haruuji, fourth Koga kubō
- Ashikaga Yoshitsuna, Sakai kubō, father of Ashikaga Yoshihide
- Nagao Harukage, deputy military governor of Echigo Province, older brother of Uesugi Kenshin
- Oda Nobuhide, bushō in Owari Province, father of Oda Nobunaga
- Matsunaga Hisahide, bushō in Yamato Province
- Matsudaira Kiyoyasu, bushō in Mikawa Province, grandfather of Tokugawa Ieyasu
- Shiba Yoshimune, military governor of Owari Province
- Imagawa Ujiteru, military governor of Suruga Province
- Ōman-dokoro, mother of Toyotomi Hideyoshi and Toyotomi Hidenaga
- Tachibana Dōsetsu, bushō in Bungo Province, senior retainer of the Ōtomo clan
- Kakizaki Kageie, bushō in Echigo Province, senior retainer of the Uesugi clan
- Sanada Yukitaka, bushō in Shinano Province, senor retainer of the Takeda clan
- Shimazu Takahisa, sengoku daimyō of Satsuma Province
- Hosokawa Harumoto, deputy shōgun
- Amago Haruhisa, sengoku daimyō of Izumo and Iwami provinces
- Keiju-in, wife of Ashikaga Yoshiharu and mother of Ashikaga Yoshiteru and Ashikaga Yoshiaki
- Hōjō Ujiyasu, sengoku daimyō of Sagami Province, son of Hōjō Ujitsuna
- Oda Nobumitsu, bushō in Owari Province, younger brother of Oda Nobuhide
- Ōgimachi, 106th emperor
- Imagawa Yoshimoto, sengoku daimyō of Suruga Province
- Date Harumune, bushō in Mutsu Province, 15th lord of the Date clan
- Takeda Nobumasa, military governor of Kai Province
- Mōri Hiromoto, bushō in Aki Province, father of Mōri Motonari
- Sesshū, artist and Zen monk who trained in China
- Kyōgoku Kimune, head of the samurai-dokoro, or office of security for the bakufu
- Takeda Nobutsuna, military governor of Kai Province
- Hosokawa Masamoto, deputy shōgun of the Muromachi bakufu – assassinated by his retainers
- Hosokawa Sumiyuki, adopted son of Hosokawa Masamoto – killed as retribution for the assassination of Masamoto
- Shimazu Tadamasa, military governor of Satsuma Province
- Kyōgoku Masatsune, military governor of Izumo Province
- Shiba Yoshitoshi, military governor of Owari Province
- Uesugi Akisada, deputy shōgun of the Kantō Region
- Yanagiwara Kazumitsu, senior official of state affairs
- Yoshida Kanetomo, founder of Yoshida shindō, a branch of the Shintō religion that incorporates elements of Buddhism, Taoism, and Confucianism
- Ashikaga Yoshizumi, the 11th shōgun of the Muromachi bakufu
- Chōsokabe Kanetsugu, a leader of influential families in Tosa Province, father of Chōsokabe Motochika
- Asakura Sadakage, sengoku daimyō of Echizen Province, ninth head of the Asakura clan
- Yamana Toyoshige, military governor of Inaba Province
- Shiba Yoshihiro, military governor of Owari Province
- Oda Tatsusada, deputy military governor of Owari Province
- Ichijō Fuyuyoshi, kanpaku, or chief councilor to the emperor
- Shimazu Tadaharu, military governor of Satsuma Province
- Mōri Okimoto, bushō in Aki Province, older brother of Mōri Motonari
- Utsunomiya Shigetsuna, military governor and sengoku daimyō of Shimotsuke Province, grandfather of Utsunomiya Hirotsuna
- Satake Yoshikyo, sengoku daimyō of Hitachi Province, great-grandfather of Satake Yoshishige
- Shimazu Tadataka, military governor of Satsuma Province
- Toki Masafusa, military governor of Mino Province
- Hōjō Sōun, sengoku daimyō of Sagami and Izu provinces, father of Hōjō Ujitsuna
- Miyoshi Yukinaga, bushō in Awa Province, served Hosokawa Sumimoto
- Hosokawa Sumimoto, adoptee of Hosokawa Masamoto
- Rokkaku Takayori, military governor and sengoku daimyō of Ōmi Province