Duchess consort of Brittany

A royal consort is the spouse of a ruling monarch. Consorts of monarchs in the Duchy of Brittany and its predecessor states had no constitutional status or power, but many had significant influence over their spouse. Listed are the wives of the Dukes of Brittany (some of whom claimed the title of King of Brittany) who were styled Duchesses of Brittany. Although there were six suo jure Duchesses of Brittany, the husbands of those duchesses were jure uxoris dukes and not consorts. Brittany is no longer a duchy and the title is currently not being used by the defunct Royal Family of France, so the position of Duchess of Brittany is vacant. Little is known about the duchesses whose husbands reigned prior to the year 900 besides their names.

Not all wives of the monarchs became consorts, as they may have died, been divorced, or had their marriage declared invalid prior to their husband's accession to the throne, or married him after his abdication. Such cases include

The succession was interrupted by the Norman occupation (907–937)

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