Long War
In the days of the Long War, Phyphor and other wizards had defeated the Swarms, here on the southern border of Estar. They had defeated the Swarms, but only with the help of a storm that had raged in from the Central Ocean – a storm so fierce that the legends later made said it had shaken teeth from jawbones and set the mountains to creaking. Certainly it had scattered the Neversh, breaking their strength.
It had been so close.
Only the storm had saved them
If the Swarms had broken through, they could have spread north to the continent of Tameran and west to the Ravlish Lands. As it was, the Swarms had been driven back to the Deep South, where the wizards had built the flame trench Drangsturm and the chain of castles where the Confederation kept watch, and was pledged to keep watch forever if need be.
-Book 1, The Wizards and the Warriors (Wizard War)