From Ancient Origins:
In the midst of the Hundred Years War between England and France, an enraged French woman named Jeanne de Clisson took to the sea with a fleet of warships, where she mercilessly hunted down ships of King Philip VI to avenge her husband’s death. For her ferocity, she eventually acquired the name The Lioness of Brittany. Jeanne and her crew would slaughter the crew of the King’s ships, leaving two or three sailors alive, so that the message would get back to the King that the Lioness of Brittany had struck once again.
It should be noted that actual verifiable references relating to Jeanne’s life and exploits are limited, though they do exist. Historical records include a French judgement of late 1343 condemning Jeanne as a traitor and ordering the confiscation of her lands. In 1345, records from the English court indicate Edward granted her an income from lands he controlled in Brittany and she is mentioned in a truce drawn up between France and England in 1347 as a valuable English ally. There is also a 15 th century manuscript, known as the Chronographia Regnum Francorum, which confirms some of the details of her life.
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