Kaneyama Castle is located on the 273-meter Mount Kojo next to the Kiso River in former Mino Province, at the northeastern end of the Nōbi Plain near the center of modern Gifu Prefecture.

Secondary and tertiary enclosures were to the west of the inner bailey, using the natural slope of the mountain and masugata box-gates, and stone walls for defense.

[4][5][1] Nagayoshi was noted for his violent temper and ruthlessness in battle, even to the point of killing men on his own side who got in the way of his target.

Two years later, Nagayoshi and his father-in-law Ikeda Tsuneoki decided to support Toyotomi Hideyoshi over Oda Nobukatsu and seized Inuyama Castle across the Kiso River in Owari Province.

To protect his rear against the attack by Tokugawa Ieyasu, Nagayoshi reformed Kaneyama Castle with additional dry moats and clay ramparts.

Before the battle, Nagayoshi left a will stating that in case of his death, Kaneyama Castle was to be assigned to one of his generals, and that under no circumstances was his younger brother, Mori Tadamasa to inherit.