The "late Earl of Oxford" whose library was the source of the texts could refer either to Robert Harley, 1st Earl of Oxford and Earl Mortimer (died 1724), or to his son, Edward Harley, 2nd Earl of Oxford and Earl Mortimer (died 1741). A passage at the beginning of the first volume emphasizes the role of Robert Harley, the first earl, in the creation of the library:
