Yūki Castle

Yūki Castle is the ruin of a medieval castle located in Yūki City, Ibaraki Prefecture. It was the principal stronghold of the Yūki clan, who took root in Shimousa Province (present-day western Ibaraki Prefecture), from the Kamakura period into the early Edo period. Built at the northeastern tip of a plateau facing the Tagawa River to the north, the castle is now developed as a castle-ruin park where earthworks and moat traces remain. It is especially known in Japanese history as the stage of the "Yūki War (1440–1441)" that followed the "Eikyō Uprising (1438–1439)," and it stands as a symbol of the power struggles of the Kamakura kubō and the final resistance of eastern warriors.

Yūki Tomomitsu (1168–1254) was the son of Oyama Masamitsu, a powerful local family of Oyama in Shimotsuke Province whose ancestor was Fujiwara no Hidesato. Minamoto no Yoritomo placed his trust in Tomomitsu, and he became a prominent vassal of the Kamakura shogunate. Thereafter, the Yūki clan maintained its power centered on Yūki district of Shimousa Province, and remained a leading warrior house of the Kantō region through the Nanboku-chō and Muromachi periods.

The greatest moment in the castle's history was the "Yūki War (1440–1441)." When the Muromachi shogunate (Ashikaga Yoshinori) destroyed the Kamakura kubō, Ashikaga Mochiuji, in the Eikyō Uprising, Mochiuji's surviving sons Yasuōmaru and Haruōmaru were sheltered by Yūki Ujitomo, and the clan raised troops aiming to restore the Kamakura kubō. Yūki Ujitomo and his son Yūki Mochitomo took refuge in Yūki Castle with Haruōmaru and Yasuōmaru, but the castle was surrounded by the shogunate's massive forces. After about a year of siege, the castle fell. Yasuōmaru and Haruōmaru were captured by the shogunal forces and executed during their transport. The Yūki War is passed down to later generations as a symbolic conflict in which the contradictions between shogunal authority and the local warriors of the east erupted.

During the Sengoku period, the Yūki clan survived skillfully amid pressure from the Hōjō and Uesugi clans, and maintained relations with Oda Nobunaga and Toyotomi Hideyoshi during the Tenshō era. In Tenshō 18 (1590), Yūki Hideyasu, the second son of Tokugawa Ieyasu, succeeded the Yūki clan as adopted heir of Yūki Harutomo and became lord of Yūki Castle. After Sekigahara, he was transferred to the Echizen (Fukui) domain. The castle was temporarily abandoned after that, but the Mizuno clan was enfeoffed in Genroku 13 (1700), the castle was revived in Genroku 16 (1703), and it survived until the Meiji Restoration.

Today the Yūki Castle ruins are preserved as a castle-ruin park within the city, where earthworks and moat traces remain. Yūki City has been known since the Edo period as a production center of "Yūki-tsumugi" silk textiles. It is a distinctive city where the silk-weaving tradition, which is registered as a UNESCO Intangible Cultural Heritage, overlaps with the history of a medieval castle town.