here's an idea I had: this world should still have a history.
so this is (in addition to the thing buried in the Sahara) my contribution:
The graid reached the height of power at some point a long time ago, with several focused and enlightened nations, spread far across the entire western hemisphere. reconstructing the designs ancient technology, even up to a few floating airships and uncovering the worst creation of the gone. then one group, led by a particularly orderly man, decided every place and person should be them. some disagreed. then, almost entirely amongst themselves, they annihilated eachother and everything they had built.*
this sudden unmaking of generations of life, coupled with the reproduction rate of about one new graid every thousand years (thats total, for all graid everywhere), means the graid are a dying species. they are already a rare and curious sight. eventually they will disappear entirely.
*(thus, southeast Asia has more flat and open plains than it used to, the Balkans have unusually high radiation levels, and Iran is more underwatery than it should be.)