Korea

The peninsula's own long argument over how many kingdoms it took to become one: a founding state old enough to be legendary, three rival kingdoms and the confederacy that never quite joined them, a northern successor state historians nearly forgot, and, eventually, the one dynasty that outlasted every rival before it by five hundred years.

The line below is a time axis. Position on it is date, so concurrency is visible: concurrent polities sit side by side rather than in sequence.

4 sourced edges run between this region and another, to Han Empire, Tang Empire and Liao Empire. Those are not drawn on this line — a thread that crossed regions would assert a sequence nobody cited — but they are on each polity’s own page.