The Ring and the Cross — Barbara Rogers

The Ring and the Cross is a fictional account of real events in sixth-century France, when the Christian Middle Ages was forming. The lives of the poet Fortunatus, the warrior queen Brunhild, and Radegund, a queen-turned-nun, are woven together in a tapestry of passion, political struggle, and the pursuit of holiness. All three figures see the events of their time from a different perspective.
Fortunatus grows from being a playboy poet to become the saintly bishop of Poitiers, under the spiritual guidance of his beloved St. Radegund. Brunhild tries to recreate Roman order and central government in the brutal Merovingian era and falls afoul of decentralizing historical forces beyond her control. She becomes the tragic Brunhild of the Ring legend and loses her husband Sigibert to the treachery of another woman, on whom she swears vengeance. The main historical basis for the book is The History of the Franks, an eyewitness account by Bishop-Saint Gregory of Tours.