Fulk IV, Count of Anjou
In 1096 Fulk wrote a history of Anjou and its rulers titled Fragmentum historiae Andegavensis or "History of Anjou."  Only the first part of the history still exists. It describes Fulk's ancestry. The second part was thought to cover Fulk's own rule. This part has not been found. If he did write it, it is one of the first medieval works of history written by a layman.