Joanna of Flanders (c. 1295 - September 1374) was consort Duchess of Brittany by her marriage to John IV, Duke of Brittany. She was daughter of Louis, Count of Nevers and Jeanne of Rethel and sister of Count Louis I of Flanders. She married Duke John IV in March 1329. When her husband died in 1345 in the midst of the Breton War of Succession, … Wikipedia
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