In the first place, Tanba, Tajima and Tango were divided up into two prefectures by people like Toshimichi OKUBO in the Meiji government who wanted to strengthen centralized control, ignoring their regional similarities.
そもそも丹波は、中央集権体制を進める明治政府の大久保利通らにより、但馬・丹後を含め似通った地域性を無視して2府県に分けられた。