I'm afraid the jury's still out on that one.
The Crystalline Dominion sits at the heart of Valisthea, built around the tallest of all the Mothercrystals, Drake's Tail. Many bloody battles were fought for control of this small plot of land due to its strategic importance, till the warring realms finally agreed to an armistice. As part of the peace treaty, the islands around Drake's Tail became an autonomous dominion led by a council of representatives from the surrounding nations—each realm enjoying equal claim to the Mothercrystal's blessing. No Dominant makes their home there.Official description
The Crystalline Dominion (クリスタル自治領, Kurisutaru Jichiryō?, lit. Dominion of Crystal) is an autonomous island dominion in the world of Final Fantasy XVI built around the tallest Mothercrystal, which is also depicted on its emblem along with the four Dominant-led nations' emblems.
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