The kanji for Wanouchi (輪之内) literally translates to "within in a circle." This name is derived from the fact that Wanouchi is situated between the Ibi River and the Nagara River. Historically, these two rivers ran together and the area known as Wanouchi today was one of many ring-levees in the middle of the river. Naturally, these levees were prone to frequent flooding and so the waters had to be diverted. Hence, Wanouchi's physical environment and history has been greatly shaped by the constant threat of floods.

In 1754, the Edo (modern Tokyo) Shogunate, under Shogun Tokugawa Ieshige, ordered the rich and powerful Satsuma feudal lord, Shimazu Shigetoshi (whose great wealth was regarded as a threat to the Shogunate) to send his samurai and resources to the Gifu area. Their task was to build embankments in order to divert the rivers. It seems the Shogun hoped that this project would weaken the Satsuma lord's power. This becames known as the Hōreki Age River Improvement Incident.

The construction of these banks was extremely dangerous and difficult. It is said that a human sacrifice was made in the Wanouchi area during the construction when a local retainer voluntarily gave his life by remaining under the rushing waters in order to keep a foundation pillar from moving until it could be secured from above. As well as aiding in the construction, this sacrifice was also treated as an offering to the gods ensuring the successful completing of the project. In Japanese, this sacrifice is referred to as hitobashira (人柱^?) meaning "human pillar."

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