Interesting character, it might be good to do a piece of work on him. According to Wikipedia, he was a Norman adventurer, lord of NE Wales and for a time, lord of all N Wales. So a pretty exciting guy.
I’m reading “The Normans in Britain” by Walker, and Rhuddlan seems to keep popping up. He’s mentioned in the Domesday Book alongside Rhys ap Tewdwr of Deheubarth for paying William the Conqueror £40 pa. He was very influential in that Norman success depended upon him in the 1070s and 80s. His castles at Rhuddlan and Degannwy were the base of trouble for much of Gwynedd.
There’s load more about this guy. I’m not sure whether to spend time digging deeper? Maybe another time. But definitely a guy to keep an eye on.