Geoffrey, Duke of Brittany

Geoffrey, Duke of Brittany (September 23, 1158 - August 19, 1186) was the fourth son of King Henry II of England and Eleanor of Aquitaine. In July, 1181, he married Constance, daughter of the Duke of Brittany, inheriting the title through her a few months later.

Geoffrey never got to rule England, because he was killed in a tournament before his older brother Richard the Lionhearted died.