One of the first planes that was fully usable after the Planar Wars, Serriya was build from scratch by Keolah, and the other Builders. All the major Builders went off to bring the other planes out of chaos, but a few less powerful ones, led by Dreamshifter, helped flesh out Serriya.
Because it is a young plane, Serriya has little history. It has never seen a real war, and even battles are few and far between. It has, however, something that no other plane really has: Gods. The Serriyan Gods and Goddesses are real beings, though they are really not much more powerful than the average Elkandu. Why they exist at all is a mystery, but they run Serriya now, and seem to be doing an acceptable job thus far.