There are two theories in terms of the establishment of Takakusa Country; the theory that 水依評 became Takakusa County, based on "Koshi" which states '始壊水依評、作高草郡,' and another theory that 水依評 was divided into two counties, Homi and Omi to establish Takakusa County.
高草郡設置に関しても『古志』には「始壊水依評、作高草郡」とあって、水依評がそのまま高草郡になったのか、水依評を法美・邑美の2郡に分け、別に新たに高草郡を設けたのかで説が別れている。