The name Akō first surfaced during the Nara Period, in the area historically known for its salt production. During the Edo Period, advancements in salt production flourished. The Ikeda family, who lived in Himeji Castle, played a crucial role in this development by acknowledging the strategic significance of Akō, situated on the border of neighboring regions.

However, history unraveled unexpectedly when the lord of the Ikeda clan fell into madness, resulting in a grave incident that led to their downfall. The Asano clan then stepped in as the new lords of the region.