Originally posted by us271934-Слава Україн:

Without any earth walls or fences would he chase you around the Black Forest until you killed him? This place is but a 30 second jog to the Plains with a Fuling village about 30 more seconds from the border. One of my main goals was to not provide a squeeze play situation lol

He doesn't chase you. You can run away until the health bar disappears and you're free of him. He doesn't regen either so you can come back the next day and finish the job.
I actually summoned two Elders by accident and they hugged each other and didn't attack me or moved until I killed one of them.