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).
Peerage law
For the early part of English history, peers sometimes surrendered their peerages to the Crown. Most surrenders occurred during the early years of the nation, but surrender occurred as late as 1640, when Roger Stafford, 6th Baron Stafford was ordered to surrender his dignity to the Crown in return for eight hundred pounds sterling. Later that year, however, the House of Lords, in order to guard the position of its members, which had been threatened by the power to order surrenders of peerages, resolved, "(i) That no person that hath any Honour of him and a Peer of this Realm, may alien or transfer the Honour to any other Person, (ii) That no Peer of this Realm can drown or extinguish his Honour, but that it descends to his descendants, neither by Surrender, Grant, Fine, nor any other conveyance to the King."