In the battle of Kashii, a contingent of forces loyal to Toyotomi Hideyori, lord of Ōsaka, attempted to besiege Wakayama Castle, which was controlled by Asano Nagaakira, an ally of the shōgun.

The attackers were led by Ōno Harunaga, Ban Naoyuki, and Okabe Noritsuna.

Tachibana Muneshige, who served as military advisor of the second shogun, Tokugawa Hidetada,[1] has correctly predicted the movements of the general of Toyotomi, Ono Harufusa's troops and guided Hidetada's troops.

[2] Asano's garrison realized that their attackers were far from support or reinforcements, and met them in battle at Kashii, a short distance from Wakayama.

Okabe and Ban were killed in the battle, and Ōno was therefore forced to retreat back to Ōsaka.