The Endless Winter
Long ago (roughly 150-200 years ago – though no one is clear on the exact date), there was a particularly harsh winter. Some say it was supernatural. Others say it was bad luck. Rumors abound of it being caused by this demon or that god; no one is sure anymore. This phenomenon is now called the Endless Winter in legends.
The lake and river that borders Frostwatch completely froze – an event that has not occurred before or since. Huge blizzards swept over the lands. Travel became nearly impossible. Frostwatch, and the smaller cities and towns in the region, was essentially cut off from any of the southern lands. Frost giants, along with savage humans, poured from the frozen mountains to the north, and washed over the land. Frostwatch and the bordering towns were razed to the ground, the people scattered or slain.
After the destruction of Frostwatch, the winter raged on, lasting a few years. Just as no one is sure what caused the winter to last that long, sages are equally unclear on what exactly caused it to eventually end. Some say that a group of adventures traveled into the heart of the mountains and slew the king of the frost giants, and broke his hold over the land. Others say that it was just a natural phenomenon that ran its course.