後北条氏と古河公方足利氏の関係をめぐって : 芳春院殿・芳春院周興を通じて

抄録

This article seeks to clarify concretely the relationship between two powerful families in the Sengoku period, the Gohojoshi and the Ashikagashi, as part of the author's research on Kogakubo (古河公方). While rejecting such explanations of these families' relationship as one of compromise or envelopment, theories which ignore the strained relationship between these families, the author examines step by step the strained relations between these two families. He concludes that their relationship developed in the following stages : 1.Before the establishment of marital relations 2.After the establishment of marital relations 3.After the rise of Kubo Yoshiuji (公方義氏) a.Hoshun・indono (芳春院殿) b.Hoshun・inshuko (芳春院周興) 4.The era of Hojo Ujiteru (北条氏照) After the fourth stage the Gohojoshi control of the government was accomplished, and the Kogakubo Ashikagashi existed only as a symbol of authority, thus distinguishing this period from earlier periods when the Ashikagashi held real power. Stages two and three were when the Kogakubo Ashikagashi tried to maintain its power through its symbolic authority. The Gohojoshi was establishing close relations with it through marriages. Then, as a member of the family and the actual Kanto Kanrei (関東管領), Gohojoshi took full advantage of its power and sought to establish itself as Daimyo-Ryogoku-Sei (大名領国制). Thus, the Gohojoshi held a two-sided relationship with the Ashikagashi. During the third stage this two-sided relationship continued when Yoshiuji was not at all a puppet. Hoshun・indono, the daughter of Hojo Ujitsuna (北条氏綱の娘) and mother of Yoshiuji, and then later on the Zen monk Hoshun・inshuko both played important function in developing this two-sided relationship to an extreme degree. Hoshun・inshuko, as the head of the sojya (奏者), had an important role in many ways, even in the composition of formal documents, and he took an active role in changing the power structure of the kubo. Also, at this time the Esso (越相) Alliance was formed between two former rivals, Echigo Uesugishi (越後上杉) and Gohojoshi. This new alliance confirmed the relationship between the Gohojoshi and the Kubo Yoshiuji, while it also brought to an end the external function of Yoshiuji. Thereby the Gohojoshi could end its two-sided relationship with Yoshiuji and changed him into just one of the feudal lords under the Gohojoshi rule. Yoshiuji survived only as a symbol of authority without any political base but for his position as an ancestor of the Ashikagashi.