- Hojo Soun vs. Miura Yoshiatsu
- Date: 1516
- Location: Sagawa province
- KIA: Miura Yoshiatsu, Miura Yoshimoto
- Siege
Miura Yoshiatsu and his son Yoshimoto allied with the Ogigayatsu branch of the Uesugi and opposed the Hojo's activities in Sagami. Yoshiatsu's attempts to reduce the Hojo's forward forts failed, however, and strife within the Uesugi allowed the Hojo to turn their full attention on the Miura. In September 1512 Hojo Soun was in a position to lay siege to Yoshiatsu at Okazaki Castle, a critical part of the Miura's defense of the Miura Peninsula. Yoshiatsu was forced to quit Okazaki and retreat to Arai, a castle held by his son Yoshimoto. The Hojo and Miura skirmished near Kamakura on a number of occasions as Soun reduced the Miura's remaining outer forts, effectively bottling up Yoshiatsu at Arai. With the Miura reduced to only Arai, Soun was content to let them 'wither on the vine' for almost three years. Finally, in 1516, Soun ordered an all-out attack on the starving defenders of the castle and Yoshiatsu and Yoshimoto, after a brave stand, both committed suicide. Yoshimoto is famed for having cut off his own head, an act which, whether true or not, is said to have greatly impressed the Hojo