William was the son of Conan IV of Brittany and Margaret of Huntingdon. Little is known of his life but he is thought to have died around 1200. He did not inherit the dukedom of Brittany from his father, instead it was inherited by his sister’s husband, Geoffrey, son of King Henry II of England.
Family tree for William showing:
parents 
siblings 
Published May 18, 2020 @ 5:10 pm – Updated – [last-modified]
Harvard Reference for this page:
Heather Y Wheeler. (2020). William of Brittany d c1200. Available: https://www.treesofblue.com/william-of-brittany-d-c1200. Last accessed September 15th, 2024