“ There is a land far to the east that is a great, desolate, near-empty wasteland home only to barbarians, ghosts and monsters. Many nations launche expeditions to this land, seeking to find the rumored-at treasures and riches beyond it's outer fringe.”
“ (Apologies to GRRM and HBO)
A group of northerners want to bring the Old Gods back to the south. They grow cuttings from the white trees seeking the blessings of the Old Gods on the project, and when the saplings are big enough, they carve faces in them and secretly plant them in forests all over the south, to extend the 'reach' of the Old Gods.
The plan works of course, but the trees are *baby gods*, and behave as such when invoked.”