Around the same time, humans around the world were preparing for the big war that was going to come. Small skirmishes happen all the time at the border between human and devil's lands.
Other races had also noticed the pending tension between the two species. Devils and humans made up the majority of the Edolas population, but there were also Eleves, Dwares, and other species which, in total, equal the population of humans.
While the Devil was hated by other species that dwelled on the continent, however, they didn't think well of humans as well.
Humans had a tendency to betray their own race and join the Devil. It is even possible for humans to betray their own race, and other races cannot trust such races. Many Devil Contractors had also killed many Elves and other species causing them to feel hatred towards humans.
