Sebastien de Luxembourg, vicomte de Martigues

Sebastien de Luxembourg, duke of Penthièvre (1530-1569) was vicount of Martigues, count and later duke of Penthièvre (1566–1569) and a peer of France.

He was the son of François de Luxembourg and Charlotte de Brosse, daughter of René de Brosse. Nephew of Jean de Brosse, duc d'Étampes, he was allowed to inherit his uncle's taken estates and was subsequently created the 1st Duke of Penthièvre.

He participated at the Siege of Leith in 1560, but was killed on November 19 1569 at the Siege of Saint-Jean-d'Angely.
His only daughter and heiress Marie de Luxembourg married Philippe-Emmanuel de Lorraine, duc de Mercœur, the rebel in Brittany.

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