Geoffrey II Duke of Brittany

Geoffrey II, born on 23 September 1158, was the fourth son of Henry II of England and Eleanor of Aquitaine. He became Duke of Brittany and Earl of Richmond through his marriage to Constance, Duchess of Brittany, in July 1181. Geoffrey was involved in his father's political maneuvers in Brittany, which included the forced abdication of Conan IV in favor of his daughter Constance, Geoffrey's future wife.

Geoffrey was known for his rebellious nature, participating in revolts against his father, Henry II. He joined the first revolt at age fifteen and later reconciled with his father in 1174. Geoffrey was a close ally of Philip II of France, and there is evidence suggesting he planned another rebellion with Philip's support in 1186.

Geoffrey died on 19 August 1186 at the age of 27, reportedly trampled in a jousting tournament, and was buried at Notre Dame de Paris. After his death, his widow Constance was arranged to marry Ranulf de Blondeville, who briefly became Duke of Brittany.