Names don't just come out of nowhere. And at some point the Ritual of Thorns clearly was undone, since none of the IEs have thorns growing out of their sides, and they aren't compelled to return to the wood after a year and a day. And, at best guess from what else we know of the region, Barsaive would have been in the general area of the Black Sea. The fact that sometimes there is a 'cultural memory' of things that we no longer understand, but realize were important, once. Just in Shadowrun/Earthdawn lore, you have plenty of examples of this, such as the fact that Dragons and metahumans appear much like people always thought they might, or ideas such as Atlantis sinking beneath the waves (those Orichalcum pillars supporting Thera gave out eventually), or even tales of spirits and dragons and the like that sounded like fairy tales. Even in real life, we have these kinds of cultural memories. The history of today becomes the legends of tomorrow and the myths of the day after. To give an example, take the Battle of Thermoplye. The story has grown in the telling, and certainly the battle was nothing like what you saw in 300, but elements remain true. In another two thousand years, who knows what we will remember of that battle?
