Priestess of Avalon tells the story of the British princess Eilan, known to the Romans as Helena. Helena's journey begins in Avalon when she falls in love with a Roman officer destined for imperial greatness. But she will find that forbidden love comes at an unexpected cost; she is banished from Avalon. We follow Helena as she grows from maiden to mother to wisewoman, experiencing both joy, with the birth of her child, and loss, when politics will force her lover to choose between her and the Empire. But when her son Constantine becomes Emperor she slowly discovers that her role has gone far beyond that of the traditional mother.
Helena finds herself at the center of a crucial turning point in Western history as she seeks a way to bridge the pagan world of the Goddess and the new Christian Empire. And, as Empress-Mother, Helena embarks on a pilgrimage to the Holy Land to find the truth that transcends both the old religion and the new.