The Half-Made World - Felix Gilman

The world is still only half-made. Between the wild shores of uncreation, and the ancient lands of the East lies the vast expanse of the West---young, chaotic, magnificent, war-torn.

Thirty years ago, the Red Republic fought to remake the West---fought gloriously, and failed. The world that now exists has been carved out amid a war between two rival factions: the Line, enslaving the world with industry, and the Gun, a cult of terror and violence. The Republic is now history, and the last of its generals sits forgotten and nameless in a madhouse on the edge of creation. But locked in his memories is a secret that could change the West forever, and the world's warring powers would do anything to take it from him.

Now Liv Alverhuysen, a doctor of the new science of psychology, travels west, hoping to heal the general's shattered mind. John Creedmoor, reluctant Agent of the Gun and would-be gentleman of leisure, travels west, too, looking to steal the secret or die trying. And the servants of the Line are on the march.