Great Frost

The Great Frost is the apocalyptic event that changed the world of Frostpunk.

Many believe that the Great Frost, following the global cooling and the New Ice Age, was caused by volcanic eruptions and the impact of meteorites. However, members of the British Research Expeditions and Scientists from Winterhome uncovered that, for some unknown reason, the sun might be dimming. There is somewhat contrary evidence presented during the loading screen that mentions that the atmospheric volcanic ash blanket makes accurate readings impossible, however it is uncertain if this affected the Winterhome scientists.

One of the Relics found in Endless mode also suggests some sort of doomsday weapon might've been used, but it does so in a way that also suggest that this is purely a rumour and demands that the research efforts do not aim to prove or deny this theory and rather to "not allow such unfounded theories to distract the scientists from finding out the real reason behind the recent cooling."