In 1600, at the onset of the Battle of Sekigahara, at first, he fought on the side of the western provinces, and subsequently switched sides, fighting on the side of the eastern provinces along with Hideaki KOBAYAKAWA.
1600年の関ヶ原の戦いでは当初、西軍に与していたが小早川秀秋の寝返りに呼応して東軍に寝返った。