What purpose did the isle Azys La serve? Main Storyline Spoiler.

[Delily]

What is the official lore on the Warring Triad? Obviously they are called eikons so do they have some origin in the FF games like the crystal tower and its bosses were from FF3? Just curious it's all very interesting..

For FFXIV, they were the first 3 primals the Allagan empire managed to control.