R' DovBerish Meisels, A.B.D. Warsaw - Ancestor?

So in an interview that I was watching (Emanuel Finkelstein- Emanuel "Manny" Darin - My Great Grandfather) said his Great Great Great Grandfather was the chief rabbi of Poland "Meizels". I suspect he is related through his fathers side, though I can't find anything about his father's parents (apart that his fathers fathers name was Dov Hacohen). Does anyone know how I can track back to him?