In 1361 Ujinori AKAMATSU, the forth son of Norimura AKAMATSU (Enshin) who was the Governor of Harima Province, became the ruler of Arima County and constructed Sanda-jo Castle.
1361年（康安元年）　播磨国守護だった赤松則村（円心）の四男・赤松氏範が有馬郡を領有し三田城（車瀬城）を築城。