The Course of Honor — Lindsey Davis

In ancient Rome, ambitious citizens who aspired to political power, to become one of the ruling elite -- a senator, had to follow what was known as "The Course of Honor." This course had only one unbreakable rule: a senator is forbidden to marry a slave, even a freed slave. When the soldier Vespasian meets an interesting girl in the imperial palace, he doesn't know she is a slave in the household of the imperial family. But he is inexorably drawn in by her intelligence and charisma. Yet as Vespasian slowly rises from near-obscurity and as emperor after emperor plays out their own deadly, seductive games of lust and conquest, the future is something no one could imagine. No one could believe that a country-born army man might win the throne -- no one, that is, except a slave girl who, with the future Emperor, begins a daring course of honor of her own.