Does a Zealot Barbarian need a God?

From a standpoint strictly based on the lore of the "default" setting of D&D 5e (or even previous editions, if necessary):

If, for example, an Eldritch Horror from the Far planes were to slaughter all the Gods and destroy the Weave, what would happen to a Zealot’s Barbarian Powers?

  • Would they lose the "Divine Fury" ability, as there’s no god to grant them Divine Energy?
  • Would they lose all of their subclass abilities?
  • Or would they be able to still use all of their abilities just fine, because "they simply learned to transform their rage into soul-shattering power (a.k.a. radiant damage)".

Again, i’m asking purely from the standpoint of the Lore and Setting. Since 5e is too vague, i’m fine with an anwser based on previous editions as well, like 3.5e