In the Sengoku period (period of warring states), the Naito clan appointed as Shugodai (representative of provincial shugo) established influence in Yagi, Ujitsuna ARAKI renowned for military fame established influence in Sonobe, and the Kawakatsu clan believed to be a scion of the Hata clan (however, other people have different opinions) established influence in the town area of Miyama, respectively.
戦国時代には、八木に守護代内藤氏、園部に武名の名高い荒木氏綱、美山町域は秦氏の末裔という（但し異説がある）川勝氏が割拠した。