A member of the Akechi Toyama clan of Mino Province. In 1574, when Takeda Katsuyori advanced on Akechi Castle with a force of 15,000, Toshikage, then a Buddhist monk, returned to lay life to help his young nephew Kazuyuki defend it with fewer than 500 men. Oda Nobunaga's relief force was blocked by Takeda general Yamagata Masakage, the castle fell, and Toshikage fled to Mikawa. At the Battle of Sekigahara in 1600 he fought for Tokugawa Ieyasu, recaptured Akechi Castle, and became the founder of the hatamoto Akechi-Toyama family.

A commander who combined the resolve to leave the priesthood in his clan's moment of crisis with the perseverance to reclaim his ancestral territory after more than two decades in obscurity.

The Toshikage line continued as the hatamoto Akechi-Toyama family and is also known for producing Toyama Kinshiro (Toyama Kagemoto), the famous Edo town magistrate. The ruins of Akechi Castle in Ena City, Gifu Prefecture, are a prefecturally designated historic site.