The Horigoe kubō was a political administration formed by Ashikaga Masatomo in Horigoe in Izu Province. The Horigoe kubō comprised one of several administrations in the Kantō during the Muromachi period. In some instances, this is referred to alternatively as the Horikoshi kubō. Masatomo served as the first head of the Horigoe kubō from 1457 to 1491, followed by Ashikaga Chachamaru from 1491 to 1493.
In 1457, Ashikaga Yoshimasa, the eighth shōgun of the Muromachi bakufu, devised a plan to counter the Koga kubō, Ashikaga Shigeuji, with whom he had an increasingly contentious relationship. To further his strategy, he arranged for his half-brother, Ashikaga Masatomo, to return to secular life from the Tenryū Temple in Kyōto where he had been residing as a monk, and, in 1458, to relocate from Kyōto to the Kantō to formally serve as the Kamakura kubō. Resistance to his rule, however, prevented Masatomo from entering Kamakura, so he set-up his quarters nearby in Horigoe in Izu Province. Initially, he ran his operations from the Kokusei Temple, but, in 1460, this was burned down so he moved to another location where he constructed the Horigoe palace. Meanwhile, following his ouster from Kamakura, Shigeuji settled in Koga Castle in Shimōsa Province from where he successfully governed the northern Kantō. As a result, Masatomo and Shigeuji stood as rivals for the position of the Kamakura kubō. As the Kamakura kubō based in Horigoe, Masatomo was called the Horigoe kubō while, as the Kamakura kubō based in Koga, Shigeuji was called the Koga kubō.
The Horigoe kubō included members of the Yamauchi-Uesugi and Ōgigayatsu-Uesugi families, along with Shibukawa Yoshikane and Uesugi Noritomo (the representative of the Muromachi bakufu in Kantō) and his son, Uesugi Masanori. Masatomo did not have the authority to give military orders to generals who sided with the bakufu in the Kantō; the bakufu issued orders directly. The bakufu in Kyōto held the real power, leaving Masatomo in a vulnerable position. Moreover, numerous generals in the Kantō felt a deep sense of loyalty toward Shigeuji as a blood relative of Ashikaga Motouji, the first Kamakura kubō. These circumstances prevented Masatomo from obtaining support and cooperation from influential forces in Kantō. Meanwhile, in an effort to oppose the Yamauchi-Uesugi family, Shibukawa Yoshikane named himself the secretary of the Kantō (a former name for the deputy of the Kantō), triggering an internal conflict. Masatomo claimed lands that were designated to supply rice to the military, and allocated landholdings of local landowners in Izu and Sagami provinces, leading to confrontation with the Ōgigayatsu-Uesugi family who governed Sagami. In 1462 or 1463, he lost his position owing to his differences with the Ōgigayatsu-Uesugi. This thwarted plans he had to fortify his position by constructing residences for military families from the eastern provinces near his palace in Horigoe in Izu and prevented him from establishing the governing authority of the Horigoe kubō in the Kantō.
The bakufu attempted to send forces to the Kantō, but as an outcome of persistent challenges with the Shiba clan, marked by the Battle of Chōroku from 1458 to 1459 and a disturbance known as the Buei-sōdō in 1465, daimyō from Dewa and Mutsu provinces failed to deploy. A break-out of the Ōnin-Bunmei War vanquished any expectations that the bakufu would dispatch forces to the Kantō. A rebellion by Nagao Kageharu posed a threat to the Yamauchi-Uesugi family, an event known as the Revolt of Nagao Kageharu. The Ōgigayatsu-Uesugi were swept-up in the conflict, so that a concerted effort by the bakufu to overthrow Shigeuji became untenable. In 1482, the bakufu finally reached a settlement and Shigeuji was pardoned on the condition that Ashikaga Masatomo remain in control of Izu Province. Consequently, Masatomo governed this one province rather than the entire Kantō as originally planned.
Thereafter, Masatomo took advantage of resistance toward the bakufu, devising a plan to depose his nephew, Ashikaga Yoshiki, who was serving as the tenth shōgun, and replace him with his youngest son, Ashikaga Yoshizumi, but before he could act upon his plan, Masatomo died of illness in 1491. Masatomo’s second son, Ashikaga Jundōji, was chosen to be his successor, but was later killed, along with his mother, by a half-brother named Ashikaga Chachamaru, who then became the next Horigoe kubō.
In 1495, the main quarters for the Horigoe kubō known as the Horigoe gosho was attacked by Imagawa forces under the command of Ise Sōzui (later known as Hōjō Sōun), a maternal relative. This resulted in the ouster of Chachamaru. Under one theory, Yoshizumi became the eleventh shōgun by means of the Meiō Political Incident, while Chachamaru was eliminated owing to the killing of the natural mother of the shōgun. This may have been orchestrated by Uesugi Sadamasa. Consequently, the Horigoe kubō ended after just thirty-eight years. Thereafter, Chachamaru sought to reclaim Izu with support from the Yamauchi-Uesugi family and the Takeda clan, but, in the autumn of 1498, he was apprehended by Sōun in Kai Province and killed himself. There are various theories concerning the timing of dissolution of the Horigoe kubō, but it is certain that the Ise clan, as predecessors of the Gohōjō, took control of Izu Province in the latter half of the fifteenth century, by which time the Horigoe kubō was gone and the Koga kubō had taken on the lineage of the Kamakura kubō.
Following a short period of governance under Chachamaru, the Horigoe kubō dissolved while the pedigree was inherited by the shōgun family in Kyōto. The bloodline of the Horigoe kubō continued from Ashikaga Yoshizumi (the eleventh shōgun) to Ashikaga Yoshiaki (the fifteenth shōgun). This continues to current times through the Hirajima kubō family (also known as the Awa kubō based in Awa Province in Shikoku).
When Masatomo moved from Kyōto to the Kantō, he had no previous connections to the area, so, unlike the Koga kubō that inherited the territory formerly governed by the Kamakura kubō, Masatomo was required to establish a new economic base. To resolve this problem, in 1463, he removed Shibukawa Yoshikane from his position notwithstanding the support that Yoshikane provided to the Horigoe kubō after its inception. Masatomo was then able to continue governing for the next three decades.
Viewed as important to the establishment of his economic base, Masatomo resided in the Enjō Temple in Nirayama in the Hōjō area of Izu which was the former residence of the Kamakura-Hōjō clan. After the collapse of the Kamakura bakufu, a woman named Kakukai Enjō converted the property into a temple for nuns. Afterwards, it was maintained by the Yamauchi-Uesugi family who possessed the surrounding lands. These landholdings were prized owing to a scarcity of grain-producing plains in Izu and the location adjacent to the Shimoda Road and Kano River. The area was vital for both sea-based and ground-based transport. Therefore, the Enjō Temple served as an effective base for the exercise of authority in the northern portion of Izu. Masatomo may have further benefited from the deep relationships between the Muromachi bakufu and the temples and shrines in Kyōto of which there were few in the Kantō.
Close retainers who came from Kyōto seized lands in Izu owned by temples and shrines based in Kyōto as well as the five ranking temples of the Rinzai sect in Kamakura (the Kenchō, Engaku, Jufuku, Jōchi, and Jōmyō temples), managing them as their own holdings. A bugyōnin, or commissioner, named Fuse Tamemoto, garnered control of the Yasuhisa district owned by the Shōmyaku monastery of the Shinnyo Temple based in Kyōto and the Kanō district owned by the Jōchi Temple of Kamakura. Meanwhile, Asahi Norisada took over the Ukaga and Shimoda districts owned by the Jizō monastery of the Daigo Temple in Kyōto. These actions strengthened the economic base of the Horigoe kubō, but bred disorder in the Kantō, undermining support for the governing authorities.