The Shattering is not exactly geography, but more a violation of geography. For several months prior to the Long Night, there was an unprecedented storm raging in the eastern ocean. It blocked passage and even swallowed the last treasure fleet returning to Aeridor. Many lives were lost and sailors feared the passage may never be open again.
And then there was the Long Night, when the Waystones were shattered and alien forces invaded the Hesperean Sea and unleashed untold horrors for eight sunless days. Naught was heard from the Old World and again people feared they would be abandoned.
When dawn finally came slim hope returned. But then people slowly became aware that they were truly alone. Ranging ships came upon walls of mist that could not be penetrated. Magical communications that had been set up to Old World magicians reached no one. Those few with the power to teleport without the Waystones could not focus their magic to such great distances. Even the secret ways of the planes were blocked— there was no way to reach the world they had come from.
For nearly three years there was no contact between the Hesperean Sea and the lands across the ocean, even the gods themselves could not easily pierce the veil that separated the two worlds. And then — nearly as mysteriously as it happened — the wall came down.
Monumental waves and fierce storms crashed against the shores that spring, but they were merely the remnants of the barrier that kept the workds apart. Communication resumed, and a few ships made the journey from the old world that spring. The dolmen waystones had been destroyed — and deemed to risky to repair — so magical transport has been limited.
But with the coming of the new spring and changing tides, many are setting sails west to restore this new world.