Guillaume Ier de Léon

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• Deceased in 1316

Parents

• Hervé V de Léon, alias Le Vieux ( - 1305), chevalier, seigneur de Châteauneuf-en-Thymerais
• Jeanne de Rohan

Family

• Married in 1301, with Catherine de La Roche-Bernard, issuing
  • Guillaume II