Anne becomes sovereign Duchess of Brittany, becoming a central figure in the struggle for influence that leads to the union of Brittany and France.

Anne of Brittany was reigning Duchess of Brittany from 1488 until her death, and Queen of France from 1491 to 1498 and from 1499 to her death. She was the only woman to have been queen consort of France twice. During the Italian Wars, Anne also became Queen of Naples, from 1501 to 1504, and Duchess of Milan, in 1499–1500 and from 1500 to 1512.

This is a list of rulers of Brittany. In different epochs the rulers of Brittany were kings, princes, and dukes. The Breton ruler was sometimes elected, sometimes attained the position by conquest or intrigue, or by hereditary right. Hereditary dukes were sometimes a female ruler, carrying the title duchesse of Brittany. Its principal cities and regions were ruled by counts who often found themselves in conflict with the Breton ruler, or who became the Breton ruler.

The union of the Duchy of Brittany with the Crown of France was the culmination of a political process begun at the end of the 15th century in the wake of the Mad War. It resulted in the Edict of Union of 13 August 1532 and the incorporation of the duchy into the Crown lands of France, a critical step in the formation of modern-day France.