Imagawa Clan (今川氏)
The Imagawa clan was a samurai family in Japan. The real family name was Genji (Minamoto clan) and the family lineage originated from a branch family of the Ashikaga clan and Kira clan traced back to Kawachi-Genji (Minamoto clan) which was one of Seiwa-Genji (Minamoto clan). Like the Kira clan, the Imagawa clan was a renshi (noble sibling) of the Ashikaga family (Ashikaga Shogunate house) and had the right of succession to the head family of Ashikaga, and therefore had a special position different from other branch lines of the Ashikaga family, such as the Shiba clan and Hatakeyama clan.
Summary
As described earlier, the Imagawa clan was a branch of the Kira clan that was specially treated as goikke (head and branch family of Ashikaga) by the Muromachi shogunate family. As it was said that 'if the Imperial Palace (Ashikaga Shogunate house) ceased, Kira succeeded and if Kira ceased, Imawaga succeeded,' the Kira clan and Imawaga clan were special families that had the right of succession to the head family of Ashikaga and the Seii taishogun (great general who subdues the barbarians) if the head family of Ashikaga (Muromachi shogunate family and Kamakura kubo [shogunate] family) ceased. For this reason, members of the Kira and Imagawa clans did not become kanrei (shogunal deputy) or Samurai-dokoro (the Board of Retainers) (these positions were 'jobs of vassals' and the members of both the clans with the right of succession to the head family of Ashikaga had too high social status to be assigned to kanrei and so on). In fact, Norimasa IMAGAWA was appointed to Seii fukushogun by the Imperial Court, his son Noritada IMAGAWA got preferential treatment called 'one family name in the country' from the Muromachi shogunate family so that only he and his descendents were allowed to use the family name of Imagawa.
Suruga Imagawa clan: The main branch succeeded to Suruga no kuni shugo (provincial constable of Suruga Province) from generation to generation
Described in this article.
Totomi-Imagawa clan: A branch family of 1 with an ancestor Sadayo (Ryoshun) IMAGAWA who received a fief in Totomi Province. Refer to the Sena clan.
Hizen Imagawa clan: Also a branch family of 1 with an ancestor Nakaaki IMAGAWA who received a fief in Hizen Province. Refer to the Mochinaga clan.
Family tradition
Kamakura period
Kuniuji IMAGAWA, the second son of Osauji KIRA who founded the Kira family as the first illegitimate child of Yoshiuji ASHIKAGA (the third head of ASHIKAGA family), was given Imagawa no sho (the current Imagawacho, Nishio City, Aichi Prefecture), Aomi County, Mikawa Province) and called himself Shiro IMAGAWA (or it is said that Kuniuji was a nephew of Osauji and became an adopted son). Today, there is a stone monument of the origin of the Imagawa clan in Imagawa-cho, Nishio City, which was built by Aichi Prefecture.
Since Osauji KIRA who was an ancestor of the Kira and Imagawa clans was an older brother of Yasuuji ASHIKAGA who succeeded to the heir of the Ashikaga family, he played an important role as the Ashikaga clan following the Kira clan.
From the period of the Northern and Southern Courts (Japan) to Muromachi period
When the Kenmu Restoration occurred after the fall of the Kamakura bakufu, Norikuni IMAGAWA, a grandson of Kuniuji, and his sons sided with the Northern Court of Takauji ASHIKAGA and distinguished themselves on the fields of battles and were appointed to shugo (military governors) of two provinces: Suruga and Totomi.
At the time of Kanno Disturbance, Noriuji IMAGAWA, a legitimate son of Norikuni, sided with Takauji ASHIKAGA, distinguished himself on the fields of battles and succeeded to the military governor of Suruga. The descendents of Noriuji inherited the military governor of Suruga as the main branch of the Imagawa family.
When Sadayo IMAGAWA, a younger brother of Noriuji, was appointed to Kyushu Tandai (local commissioner) by Yoriyuki HOSOKAWA, kanrei (shogunal deputy), and conquered Kyushu, where the force of the Southern Court was strong, but it seemed that he was displeased by Yoshimitsu ASHIKAGA. The Oei War occurred in which Yoshihiro OUCHI raised an army, but a suspicion was raised that Ryoshun instigated Ujimitsu ASHIKAGA, Kamakura kubo (Governor-general of the Kanto region), to support Yoshihiro. Although it was worth subjugation, Norisada UESUGI and so on asked for his life and he was forgiven by going up to Kyoto and apologizing Yoshimitsu. However, his presence was denied in the national political arena and he became a shugo (military governor) of half of the Totomi Province. His descendents continued living in Totomi and served the Suruga Imagawa clan after transferring shugoshiki (military governor) to the Shiba clan.
Chikanaga SEKIGUCHI, who was the father of Tsukiyama-dono who became a lawful wife of Ieyasu TOKUGAWA, was a branch of the Sena clan traced back to the Totomi-Imagawa clan.
Sengoku period (Japan)
At the end of the 15th century, Ujichika IMAGAWA who won succession dispute with the help of his uncle Soun HOJO attempted invasion upon Totomi Province, which had failed at the time of his late father Yoshitada IMAGAWA. He defeated the hostile Shiba clan and became Totomi shugoshiki (military governor). He established bunkokuho (the law individual sengoku-daimyo enforced in their own domain) and the Imagawa clan became daimyo (Japanese territorial lord).
But Ujiteru IMAGAWA, the first son of Ujichika, died young. Since Yoshimoto IMAGAWA who was a younger maternal half-brother of Ujiteru and won 'Hanakura no Ran' (Hanakura Rebellion), which was a succession dispute, and allied with the Kai-Takeda clan, he worsened the relationship with the Gohojo clan of Sagami Province, causing the 'Kato War'. The relationship was improved through the intermediation of Takeda and this evolved into the three-party alliance of Ko, So and Sun. Yoshimoto invaded Mikawa Province later to subordinate the weakening Matsudaira clan and carried out a westing policy successfully, he fought against the Oda clan in Owari Province who was eager to gain Mikawa in the 'Anjo War,' the 'Battle of Azuki-zaka' and so on, and excluded the Oda clan from Mikawa. Yoshimoto governed three provinces: Suruga, Totomi and Mikawa and occupied part of Owari Province, and the Imagawa clan reached the zenith, but he was killed by Nobunaga ODA by the attack to his headquarters in the Battle of Okehazama in 1560.
In the generation of Ujizane IMAGAWA who succeeded Yoshimoto, independence of Ieyasu TOKUGAWA in Okazaki-jo Castle of Mikawa Province affected the territories governed by Ujizane and induced estrangement of vassals from Imagawa. In battles to expedite rebels, Ujimasa took the field, but he was defeated by the Matsudaira army in Hoi County, Mikawa Province. Soon he lost Yoshida-jo Castle (Mikawa Province) and lost the dominion of Mikawa, he was disregarded by the Takeda clan to which he allied, the tripartite alliance was renounced unilaterally, and Suruga was in danger of invasion by the Takeda clan. Suruga Province and Mikawa Province were attacked from the east and west and occupied by the Takeda clan and Tokugawa clan (renamed from the Matsudaira clan) in mere several years. In 1568, Ujimasa who was sent away to Totomi Province transferred the last foothold Kakegawa-jo Castle to Ienari ISHIKAWA of the Tokugawa army and went away to Odawara to seek help from the Hojo clan together with the lord of Kakegawa-jo Castle Yasutomo ASAHINA. The Imagawa clan as daimyo (Japanese territorial lord) fell mere eight years after the Battle of Okehazama.
It is said recently that the clan collapsed because the economy of the territories worsened due to frequent wars by his father Yoshimoto rather than because Ujimasa was 'incompetent' as was generally rumored. This caused estrangement and collapse of vassals who exhibited dissatisfaction due to crisis of their life.
Edo period
Ujimasa lived in seclusion in Kyoto, his legitimate son Norimochi IMAGAWA died from a disease, and he was later employed by Ieyasu TOKUGAWA to serve the Edo bakufu and became a Shogun's retainer with a fief of 500 koku due to kindliness of Ieyasu. Naofusa IMAGAWA, a legitimate son of Norimochi, was given an additional fief of 500 koku because of his achievement as an envoy to Kyoto. The Imagawa clan survived as bakufu koke (privileged family under Tokugawa Shogunate) since then.
The family head at the end of Edo Period, Norinobu IMAGAWA, made efforts as koke to make peace with the government army and surrender Edo-jo Castle, but he lost his fief and fell after the Meiji Restoration and his first legitimate son Yoshito IMAGAWA died before him. The Imagawa clan became extinct due to the death of Norinobu in 1887. However, Takahisa in an illegitimate family lineage of the Imagawa clan was named the Shinagawa clan, became bakufu koke like the main family and left offspring.
The ancestral temple is the Hojusan Kanzen-ji Temple of Soto sect in Imagawa, Suginami Ward and the tomb of Ujimasa is also located there.