Naomasa was planning to move and build his castle in the area close to Lake Biwa, but he couldn't recover from the battle injury at the Battle of Sekigahara and died.
湖岸に近い磯山（現・米原市磯）に居城を移すことを計画していたが、関ヶ原の際の戦傷が癒えずに死去した。