能登國
Toshiie died the following year 1599, and Hosokawa Tadaoki convinced Toshinaga to support Tokugawa Ieyasu over Ishida Mitsunari and Toyotomi Hideyori. In 1600, at the time of the Battle of Sekigahara, his role was primarily to contain the forces of Uesugi Kagekatsu and Niwa Nagashige, they clash at Battle of Asai, and at the same time, to keep the forces of his younger brother, Maeda Toshimasa, ruler of Noto Province, from joining the western army.