Battle of Tadenawate
Date: Kyōroku 3 (1530)
Location: Seifukuji Castle in the Kanzaki District of Hizen Province in northern Kyūshū
Synopsis: In a bid to garner control of northern Kyūshū, the Ōuchi army led by Sugi Okikazu attacked Shōni Sukemasa at his base at Seifukuji Castle. Despite inferior numbers, the Shōni prevailed through the valiant efforts of a lightening unit led by Nabeshima Kiyohisa and Nabeshima Kiyofusa (father and son).
The Battle of Tadenawate occurred in Kyōroku 3 (1530) and was waged between the Ōuchi clan (sengoku daimyō of Suō Province) and the Shōni clan (daimyō of Hizen Province) in regard to control of northern Kyūshū.
Throughout the Muromachi period, the Ōuchi and Shōni clans were arch-rivals, competing with one another to establish a hegemony in northern Kyūshū through the office of the dazaifu, or local administrative organ of the Muromachi bakufu in Chikuzen Province. In 1497, Ōuchi Yoshioki eliminated Shōni Masasuke and, in so doing, reduced the Shōni from their former position as rulers of chinzei, or northern Kyūshū, to that of a local power in Hizen Province.
Ōuchi Yoshitaka (the son of Ōuchi Yoshioki) sought to eliminate his arch-enemy, Shōni Sukemoto (the son of Shōni Masasuke) by ordering Sugi Okikazu (the deputy military governor of Chikuzen) to lead generals in Kyūshū allied with the Ōuchi and to attack Sukemoto’s base at Seifukuji Castle in Hizen. Generals on the side of the Shōni, including Ryūzōji Iekane and Baba Yorichika, fought valiantly, but, owing to their inferior numbers, increasingly faced the prospect of a defeat. Nevertheless, through the valor of lightening unit known as the shaguma, or red bears, led by Nabeshima Kiyohisa and Nabeshima Kiyofusa (father and son) and members of the Ishii party, the expeditionary forces led by Okikazu were defeated. Ōuchi forces including Yokodake Sukesada and Tsukushi Hisakado were killed in action.
The Ryūzōji clan contributed to the victory by allying with powerful landowners from the southern portion of Saga Plains. After the battle, the Ryūzōji wielded more influence within the Shōni family, taking advantage of the opportunity to achieve the status of a sengoku daimyō.
Riding the momentum of this victory, the Shōni temporarily recovered their power, engaging in actions such as an attack on the dazaifu, or local administrative organ of the Muromachi bakufu in Chikuzen Province. However, after Sue Okifusa (the deputy military governor of Suō under the Ōuchi family) rode into Kyūshū, the Shōni’s influence began to wane again. Further, Ōuchi Yoshitaka himself led a large army on an offensive, causing even Ryūzōji Iekane to abandon his support for the Shōni.
In 1535, Sukemoto killed himself so the Shōni clan was temporarily extinguished.