Here's a quote for you from Folklore of Guernsey by Marie de Garis. ''William the Conqueror had an uncle, Mauger, Archbishop of Rouen. When Duke William married his kinswoman, Mathilda of Flanders, he was granted a dispensation by the Pope. But Mauger disapproved of the marriage to such an extent that he was excommunicated by his nephew. For this he was banished to Guernsey, that most far flung of William's domains.' It goes on to describe his marriage to a Guille, his child Michel of Bayeux etc. There are fabulous stories of your Maugers, including the beautiful Rachel.Have you read it?