Winter is Coming is the motto of House Stark in Game of Thrones, the HBO fantasy series based on George R. R. Martin's novels, which first aired in 2011. The line became closely associated with Ned Stark and the cold, guarded world of the North, and it was repeated in trailers and opening episodes until it entered everyday language. Online, creators turned it into a flexible warning for anything approaching, from snow and exam season to a rival's return. Its staying power comes from that simple structure: a short, serious promise that something unavoidable is almost here.