The Lion's Eye — Mary Gentle

Abandoned and alone, the fosterling Ilario grows up as the King's Freak, surrounded by all the pomp, intrigue, and danger of the Iberian court. Fleeing a failed treacherous attack, Ilario crosses the sea to Carthage, where the mysterious Penitence shrouds the sky in darkness. There, a strange and awful destiny awaits the would-be painter, one that spans continents and kingdoms.