Valtias Forlǫg
From ShireWiki
Valtias Forlǫg means Valtia's Fate in the Froyalanish and Wintergleamish languages. It is the name of the cataclysm of an unspecified nature that caused the collapse of the Valtian Free State which had, prior to the Forlǫg, been prospering for thousands of years.
About
Valtia was destroyed when it sank into the sea on a winter night in the cataclysmic event which known as the Valtias Forlǫg nearly a thousand years ago. None of the inhabitants of Valtia survived its destruction, save for a few families who left Valtia just before its destruction.
The House of Ettlingar Freyu escaped the disaster because the Lady Freyja had forewarned them and told them to flee to the Mysterious Isles.