At this time, when many of the warriors were determining whether to join the western forces or the eastern forces during the war council called the Koyama Counci at Shimotsuke Province, Koyama-jo Castle, Katsutoyo immediately offered his residential castle, Kakegawa-jo Castle, to Ieyasu and gained his favor.
この最中、一豊は下野国小山城における軍議（いわゆる「小山評定」）で諸将が東軍西軍への去就に迷う中、真っ先に自分の居城である掛川城を家康に提供する旨を発言しその歓心を買っている。