I am descended from this John Compton and Mary Rebecca Clark Douglass (Douglass was her first husband's surname). I am trying to find any proof or documentation that John Compton, who immigrated to America c. 1644, was a son, or brother, or any relation at all to Lord Henry Compton, Bishop of London.

If you can help me, I would really appreciate it.

This is something that everyone is searching for, and have been for many years. The tradition has something to say about a "secret marriage" but the search is still on for proof of the connection between John Compton and Henry Compton.