Panem in The Hunger Games; Eurasia in 1984; the Magisterium of The Golden Compass
Tectonic theory posits that the earth is actually a series of plates floating on molten metal. The continents used to be smashed together in a giant supercontinent that geologists call “Pangaea.” It suggests a simpler world, where you could walk from one side of the extant world to the other; it’s a world that’s almost impossible to imagine as contiguous with our own, Brazil and Nigeria next door neighbors, Russia and Alaska and Canada all one big hunting ground.
In dystopian fiction, a similar move happens: in 1984, we have neither Great Britain nor Russia nor China but Oceania and Eurasia and Eastasia. In The Hunger Games, we have Panem (a word that is probably originally a play on “panem et circenses,” the Latin for “bread and circuses”, but also nicely captures the idea of a pan-encompassing nation-state).