After that, based in Imajo, Echizen Province, he supported Kobayakawa Hideaki and Horio Yoshiharu.

In 1600 at the Battle of Sekigahara, he was under Ōtani Yoshitsugu, who led part of Ishida Mitsunari's force.

However, taking advantage of Kobayakawa Hideaki's betrayal, he switched sides with Wakisaka Yasuharu, Kutsuki Mototsuna, and Ogawa Suketada.

In 1606, looking over flooded Daimon River, in Etchū Province, he fell off a horse and died by drowning.

Takaharu changed his family name to Nagahara (永原), and became a retainer of the Maeda clan of Kaga.