Rose of the Prophet Trilogy (Weis Fiction)

The world of Sularin is ruled by twenty gods, different in aspect but equal in power. But a war rages in the heavens, one that will affect the gods, the mortals, and the immortal beings who serve them both. It is a tale of romance and magic, blending epic fantasy with Arabian adventure. Khardan, Calif of a horse-riding tribe, and Zhora, princess of a sheep-herding people, must put aside their own differences - with the help of a young spellcaster named Mathew from across the sea - before the fabled Rose of the Prophet blooms.