The Well implodes; Kalimdor is sundered

Full History

For the kaldorei empire, the Well of Eternity had been the source of an entire age of magic and political power. The Highborne's attempt to open a gateway for Sargeras turned that foundation into a danger to all Azeroth. When the resistance finally thwarted the Legion's plans, the struggle at the Well ended not in its peaceful restoration but in a catastrophic collapse. The source that had transformed the night elves could no longer sustain the world that had grown around it.

The Sundering ripped through the landmass of ancient Kalimdor. Great stretches of the continent vanished beneath the sea, leaving separated lands and islands where a single vast geography had existed before. At the center of the disaster the Maelstrom marked the lost Well's ruin. The imperial capital and much of the civilization that surrounded it were destroyed; the survivors found themselves in a physically and politically transformed world.

The shock reached beyond the night elves. Troll societies, ancient settlements, and the territories of other Kalimdor peoples had belonged to the land that was broken. The Sundering changed the routes between peoples and the geography in which their descendants would establish later states. Beneath the waves, Azshara and members of her court survived in transformed forms as naga, a consequence that would return to the surface during later wars.

After the disaster, the night-elven survivors made decisions that defined their future. Illidan's creation of a second Well on Mount Hyjal revived fears of renewed catastrophe, while the planting of Nordrassil and the Long Vigil marked a different course of guardianship. Much of Azeroth's later history unfolded across continents separated by the Sundering. The event was at once the end of the War of the Ancients, the end of Azshara's empire, and the beginning of the geographical world encountered in the original World of Warcraft.