|Date||Summer 1864 CE - Ongoing|
In the late summer of 1864, the Takayama domain, alongside it's Imperial ally the Gujohachiman's, declared war on the Shogunate Nagaoka. In a move of solidarity, the Aizu clan entered the war on the side of Nagaoka.
After two months of warfare between the Nagaoka and the Takayama, the province of North Shinano was eventually lost to the invading armies. The following winter prevented an Aizu counterattack.