Geoffrey I, duke of Brittany (born 980)

Geoffrey I, Duke of Brittany

Duke of Brittany

Geoffrey I, also known as Geoffrey of Rennes and Geoffrey Berengar, was Duke of Brittany from 992 until his death, and also Count of Rennes by right of succession. The eldest son of Duke Conan I of Brittany, he assumed the title of Duke of Brittany upon his father's death in…