Complex sentence: René I de Rohan, (1516-1552) 18 th Viscount of Rohan, Viscount and Prince de Léon, and Marquis de Blain married Isabel d'Albret of Navarre daughter of Jure uxoris King John III of Navarre and Catherine of Navarre, Queen of Navarre.
Split into simpler sentences: René I de Rohan, (1516-1552) 18 th Viscount of Rohan, Viscount and Prince de Léon, Marquis de Blain. He married Isabel d'Albret of Navarre daughter of Jure uxoris King John III of Navarre and Catherine of Navarre, Queen of Navarre.