Richard,
In the example you give above, I wouldn't link either Thomas More or Prince Arthur. The reference is to a chancery suit during Sir Thomas More's period. That's like a suit during a sovereign's reign. It has nothing to do with Sir Thomas More (nor the sovereign in my example). So don't put a link to their profiles. They could literally end up with thousands of links which are meaningless to Sir Thomas More and/or Prince Arthur.
Darlene - Co-Leader, European Aristocrats Project
P.S. When you post with regard to a medieval profile, please be sure to add the tag 'euroaristo' to your G2G post so that the project members see it. I've added the tag to your question. Thanks.