Some of one, some of the other. The gods, through their Oracle, sent word that the nations should gather at a certain place to build a temporary shelter, that they promised to keep safe until the Old Woman could be reasoned with, at the next equinox. Eventually, all the nations responded, sending men, materials, and supplies.
It was a near thing, but the shelter was built and blessed, just as the surface became truly uninhabitable; without it, none would have survived. For some reason, though, the Old Woman's anger didn't cool, and the shelter intended to last a season lasted years, and decades. And then, one of the gods began to weaken.