Dukes in the United Kingdom
Duke, in the United Kingdom, is the highest-ranking hereditary title in all four peerages of the British Isles. A duke thus outranks all other holders of titles of nobility (marquess, earl, viscount and baron).
Baron Byron
Baron Byron, of Rochdale in the County Palatine of Lancaster, is a title in the Peerage of England. It was created in 1643 by letters patent for John Byron, 1st Baron Byron, a Cavalier general and former Member of Parliament. The peerage was created with remainder to the heirs male of his body, failing, to his six brothers: Richard, William, Thomas, Robert, Gilbert, and Philip, and the heirs male of their bodies. Lord Byron died childless and was succeeded according to the special remainder by his next eldest brother Richard, the second Baron.