The Children of Ash
Exalted pg. 49
The term “the Threshold” typically denotes the ring of princedoms and city-states on the outer rings of the Inland Sea – too barbarous for the Empress to govern directly, but still civilized enough to pay tribute to the Realm. The Realm proper directly rules only the Blessed Isle. Everything else is nominally independent, a kingdom or republic paying tribute and advised by an imperial satrap.