Yasukage supported Ieyasu at Battle of Azukizaka (1564) in conflict with monks from the Ikkō-ikki religious band in Mikawa.

In 1565, he was named one of Mikawa's San-bugyô, or Three Commissioners (along with Honda Shigetsugu and Koriki Kiyonaga).

In 1573, he assisted Okubo Tadayo in a well-known night raid on the Takeda army following the Battle of Mikatagahara.

[citation needed] After the Battle of Sekigahara, from 1600–1611, he was the head of Kōkokuji Castle (10,000 koku) in Suruga Province.

[1] Yasukage lived in seclusion at Sainenji Temple in Odawara, Sagami Province, and died there.