The Percheron Saga
Book 1: Odalisque

Fifteen-year-old Boaz is the new Zar, freshly ascended to the throne of Percheron. In the turmoil following the old Zar's death, courtiers jostle and conspire to secure their positions - not least his scheming mother, the new Valide.

It seems his only genuine friends are his late father's mad jester; the head of Percheron's security; and a new odalisque purchased in the foothills as a slave for the harem.