Much of The Horse and His Boy takes place in Calormen. Back in year 180 of Narnia's existence, Prince Col, the younger son of King Frank and Queen Helen, founded the mountain kingdom of Archenland, just south of Narnia and just north of the Desert.

In the year 204, some Archenlanders migrated to the south of the Desert and founded Calormen, a nation that enjoys a warm climate. The farmlands are bountiful and Calormenes ship their fruits and vegetables throughout most of the world. However, Calormene society is based on war, not farming. Sometime in their history, these descendants of Narnia and Archenland invented a pantheon of gods, with the demon Tash as the chief god, and they came to loath and fear Aslan.

Among the evils that Calormen visits on the rest of the world are war and slavery.

The size and shape of Calormen must change often during...