The Duchy of Brittany was an independent state from 841 to 1532. Its rulers were never free from outside influence, however, with England and France competing for their favours and attention.
Brittany was conquered in 799 by emperor Charlemagne, who had after that to lead military expeditions to fight breton rebellions in 801 and 811. His son, Louis the Pious, came with his army in 818, 824 and 837. Independence from France was declared in 841 after a rebellion of Duke Nominoe who refused to accept as his suzerain, king Charles, the Bald. After a five year conflict, France recognized Brittany as a ducal state in 846 and as a kingdom in 851. Following Alan II's death in 952, Brittany is disputed between the Houses of Nantes and Rennes, until 990, when count Conan of Rennes pacifies the duchy under his control.
The Duke of Brittany (French: Duc de Bretagne) governed Brittany, a region with strong traditions of independence, including a language and a distinctive culture.
Incorporation of Brittany into the Carolingian empire ensured that the political and social institutions were similar to those prevaling elsewhere in western Francia.
The marriage of the infant Alice to Capetian cadet Peter of Dreux in 1213, began the new House of Dreux.
During the minority of Charles VIII of France, Francis II aligned himself with the Duke of Orleans and the count of Angouleme, against the regency of Anne of Beaujeu.
In July 28 Brittany was defeated in the battle of Saint Aubin du Cormier.
In the terms of the treaty, the duke was compelled to recognise himself and his duchy as a vassal of the king of France.