In the Battle of Sekigahara in 1600, he followed Hidetada who led the main Eastern army and took Nakasen-do Road, but on the way, he argued that they should attack Masayuki SANADA who belonged to the Western army and was holding Ueda-jo Castle in Shinshu and came into conflict with Masanobu HONDA and others.
慶長5年（1600年）の関ヶ原の戦い時には東軍の主力を率いた秀忠に従い中山道を進むが、途中信州上田城に篭城する西軍の真田昌幸に対して、攻撃を主張して本多正信らと対立する。