- 学習院大学人文科学論集 (ISSN:09190791)
- no.27, pp.1-61, 2018-10
This thesis aims to analyse Sobuji, which is a policy derived from Toyotomi Hideyoshi’s force and an anti-Hojo force in Kanto area. To shed light on a region formally called Shimotsuke (current Sano- a city located in the south-west part of Tochigi prefecture), paying a great deal of attention solely to Shimotsuke can internalise the history of Sobuji policy more in-depth. By scrutinising specifically, Sano clan will demonstrate its unique role in the medieval Japanese history, as its contribution has been relatively underrated in academia. Especially Tentokuji Hoen and his servant Yamagami Dogyu’s accomplishment conducted for Sano had a significant impact on the whole Japanese politics at the time. Sano was located right at the boundary between Shimotsuke and Kozuke (these two literally mean the lower and upper area). The border had a role in distinguishing the pro-Hojyo and the anti-Hojo forces. Hoen’s lineage was quite complicated but worth highlighting at the same time. Hoen was a son of Sano Toyotsuna, which namely means he was Masatsuna’s younger brother as well as an uncle of Munetsuna. Consequently, it is evident that he has a roots-wise relation to the main branch of Sano family. Although Hoen became a Buddhist priest in his early life, his strong connection with major aristocrats in the Kamigata area firmly remained in the political world. As a result, Hoen massively impacted on Japanese high society. At the time when Oda Nobunaga’s Togoku Shioki prevailed, Hoen was a diplomat of Takigawa Kazumasu, who was in charge of Kanto Otoritsugi. Hoen’s primary role was as an envoy between Oda administrations centred in the west and the anti-Hojo power in Kanto area. Following the famous Honnoji-no-hen in 1582, Hoen fought a battle with the Hojo force in Kozuke with a help of Takigawa Kazumasu as one of the sequels of Honnoji’s incident. This war, also happened in 1582, was later called as Kannagawa war. Despite his career in Kozuke, he returned to Sano and reassumed his position of a negotiator of Sano region soon after Kannagawa war. At just about the same time, the Hojo army attacked Sano that the Kanto anti-Hojo force became heightened after 1593. Therefore, the Kanto anti-Hojo force attempted to gain the favour of Toyotomi Hideyoshi to secure their safety behind Hideyoshi’s power. Toyotomi Hideyoshi, who overthrew a pro-Nobunaga force (also known as Shibata Katsuie’s troops), found these sequent to be a chance to build up his career to rule entire Japan. Hideyoshi’s interest towards situations in Kanto area reached a consensus between Kanto and Hideyoshi’s demand and supply. As a result, Kanto successfully got the most out of Toyotomi’s colossal force. Also, Hideyoshi was able to draw Kanto force into his army. Considering Sano’s geographically unique role, the Hojo group attempted to aqruire Sano to utilise the function of borders. Thus, Sano kept under pressure to stay close relations with the Hojo force. In the summer of 1575, Hoen left Sano to move to Kyoto since the Hojo force took over Sano’s rule. Hojo’s dominance over Hoen’s power resulted in Hoen’s remarkable decision to serve Hideyoshi with the intention of ousting the Hojo force from beloved Sano. As well as Hoen, Yamagami Dogyu was also in charge of Sano’s vassal in Hideyoshi’s Sobuji policy. This policy had a side that Hideyoshi’s intention to draw the Kanto anti-Hojo force. For instance, Uesugi Kagekatsu, who allied with the anti-Hojo force, took charge of a position to sort out the situations against the Hojo force through Sobuji policy. On the other hand, Tokugawa Ieyasu negotiated with the Hojo force and avoided apparently oppose to the Hojo force as Kagekatsu did. Amongst historians, the conventional appreciation of Sobuji policy has widely been recognised as Hideyoshi’s ordinance to prevail a truce all over Japan. However, this essay illustrates that Sobuji policy was established with Hideyoshi’s desire to control the Hojo force. Hoen’s extensive connection shows how military alliance had associated with the development of Sobuji policy. I hope it dawns on historians that it should be examined to fully grasp the importance of Sobuji policy for further understandings alongside Hoen’s desire to return to his dearest home, Sano.