Another theme is the status of the ruined alien race, the "qhal" (the name and its derivatives are spelled differently on each world Morgaine visits: e.g. "qujal", "khal") in relation to human beings. The qhal had been the dominant species, but were ruined by their misuse of the Gates. (The Gates themselves are relics of a more ancient, vanished race, of which it is revealed in the fourth book of the tetralogy, "Exile's Gate", Morgaine is a descendant through her father.) All the worlds described have both qhal and human inhabitants, and are at a quasi-medieval level of development (travel is by foot or on horseback, for instance), with advanced technology present but more or less hidden. It is not always explained where the human populations have come from. In "Gate of Ivrel", among the ruined human principalities of Andur-Kursh, qhal are hated and feared and few survive, though they remain powerful. In the slowly drowning landscape of "Well of Shiuan" the qhal are the dominant, cultured society and humans live in miserable squalor. In the forest world of "Fires of Azeroth", qhal and some humans have learned to live in mutual respect, carefully tending their environment (which includes another sentient race, more obviously alien): this paradisial arrangement is threatened by the irruption of the aggressive qhal-human host of refugees from Shiuan. In the world of "Exile’s Gate", a dominant qhal society keeps the human-populated areas subject through qhal governors - the exiles from the Lord's court - who have been forced to take human form.