This one is the opposite of Irish going to England.
Decades ago, before the internet, my late mother-in-law was working on her Irish ancestry, and somehow struck up a correspondence with a distant cousin in Ireland. We went to visit him, believe it was in Leitrim. He told us the Brydges family (m-in-law's grandmother was a Jane Brydges born in that area) were descendants of John Brydges, who was made a Lord, at one time the Lieutenant of the Tower of London, and he had custody of Lady Jane Grey and briefly, Elizabeth I (as princess). Apparently a Brydges was given land in Ireland. So far, still a myth. The family was C of E and spelled it the same way.
One of my relative's widow married for the second time, a Michael Faraday (actually her first husband's cousin on the other side) who was born in Clapham, Yorks. ca 1862. When he died in 1934, he was proclaimed to be the last living descendant of Michael Faraday, the esteemed scientist, whose father had moved the family to London from Westmorland, and the fact that Michael the scientist had no children, pretty well puts this family myth to rest. (I only found out about the spurious claim when I read his obit).