A type of state found in Egypt and the Levant where the rulers were recruited from the wild Turkish tribes of the Caucasus - Circassians.

This was a regime that was formed when the mercenary army of the Fatimite Khalifate based in Egypt revolted against the Khalif. They made a rule that only people recruited from the Caucasus could join the army, and that the sons of existing rulers could not inherit power. The ruler (Sultan) could not have been born in the country he ruled.

Mentioned in this Review of Fukuyama's new book as an example avoiding nepotism.

Was this an application of Ibn Khaldun's thoughts and an attempt to evade his observation that the sons of previous rulers were nearly always worse than their fathers? Another application was the Janissary Guard of the Ottoman Empire - soldiers recruited entirely from the Christian inhabitants of that Empire.

Perhaps Robert A. Heinlein's repulsive Federation in his "Starship Troopers" was based on this regime.

See Wikipedia article