Can someone give me a name for this fictional incident?

this incident is for my story. during the Edo period of japan there is this fictional town (it wasn't officially a town yet) where demons (Oni as you call them) lived with humans. there were ten demon clans and when the anti-Shogunate learned of their existence they asked (or rather threatened) for their help to overthrow the Shogunate but they refused. 2 of the clans were annihilated ( some humans were also included) completely while the eight fled. after the massacre, the town was set on fire. for years the town was abandoned until during the first year of the Meiji era the town was officially established and the remaining eight clans came back together and continued protecting the town.