Complex sentence: His maternal grandparents were Charles Paulet, 1st Duke of Bolton and his second wife Mary Scrope, natural daughter of Emanuel Scrope, 1st Earl of Sunderland.
Split into simpler sentences: His maternal grandparents were Charles Paulet, 1st Duke of Bolton and his second wife Mary Scrope. Mary was a natural daughter of Emanuel Scrope, 1st Earl of Sunderland.