Charles II

(born 1332—died Jan. 1, 1387) King of Navarra (1349–87). He acquired Normandy from John II of France by threatening an English alliance. Arrested for his treachery in 1356, he escaped a year later and regained Normandy. He pursued shifting alliances in Spain in an effort to expand Navarrese power. Charles V voided his claims in France, and the discovery of his plot to poison the French king cost him all of Normandy except Cherbourg.

Source: Encyclopedia Britannica