What is "nehwon"

Nehwon is the fictional world created by Fritz Leiber in which his heroes, Fafhrd and the Gray Mouser, adventure. It is notable for the city of Lankhmar.

"Nehwon", the reverse spelling of "No When", alludes to Erewhon.

Sundered from us by gulfs of time and stranger dimensions dreams the ancient world of Nehwon with its towers and skulls and jewels, its swords and sorceries. Nehwon's known realms crowd about the Inner Sea: northward the green-forested fierce Land of the Eight Cities, eastward the steppe-dwelling Mingol horsemen and the desert where caravans creep from the rich Eastern Lands and the River Tilth. But southward, linked to the desert only by the Sinking Land and further warded by the Great Dike and the Mountains of Hunger, are the rich grain fields and walled cities of Lankhmar, eldest and chiefest of Nehwon's lands. Dominating the Land of Lankhmar and crouching at the silty mouth of the River Hlal in a secure corner between the grain fields, the Great Salt Marsh, and the Inner Sea is the massive-walled and mazy-alleyed metropolis of Lankhmar, thick with thieves and shaven priests, lean-framed magicians and fat-bellied merchants—Lankhmar the Imperishable, the City of the Black Toga.

—From "Induction" by Fritz Leiber

Technology in Nehwon varies between the Iron Age and the medieval. Leiber wrote of Lankhmarts: "They may be likened to the Romans or be thought of as, if I may use such a term, southern medievals." About his Eastern Lands, he wrote "think of Saracens, Arabs, Parthians, Assyrians even. They ride the camel and elephant, and use the bow extensively."