Keen local historian Jon Gunson has compiled this series entitled Friday Knight - knights who fought at the Battle of Lewes - giving each a brief biography.
Very few knights died at Lewes.
This is not because they were invulnerable in their armour: a mail hauberk will not keep out a crossbow bolt, a warhammer, or even a well-aimed spear.
It was partly because a man on horseback is hard to get at, and mostly (I suspect) because they were all related. You don’t want to go home to the wife and tell her you’ve just killed her brother.
Fulk was one of the unlucky ones, and it was not cold steel that did for him. He drowned, trying to escape across the Ouse marshes.