Forests of Avalon, by Marion Zimmer Bradley

Forests of Avalon tells of an era of upheaval and change. The Roman grip on their empire was slackening; the Druidic Order – far stronger that the tiny Christian sect – was itself in turmoil. Caught in the centre of the conflict is a young British girl of druidic family, chosen to be a priestess, and a roman tribune, ambitious for power but – as the son of a British mother – torn between two cultures. This is a dramatic, illuminating tale of rebellion and religion.