What Is a Duke?

The peerage of the United Kingdom is ordered in five descending degrees: duke, marquess, earl, viscount and baron. A duke stands at the top of that ladder, and in the order of precedence a non-royal duke is outranked only by members of the Royal Family and by a handful of great officers of state. That position is the whole of the rank's constitutional meaning in ordinary life: precedence at ceremonies, a place in the recognised hierarchy of dignities, and nothing more concrete.

Dukedoms are deliberately scarce. Where baronies have been created in large numbers, particularly as life peerages since 1958, dukedoms have been created very rarely in the modern period and almost exclusively for members of the Royal Family. This scarcity, rather than any distinct legal power, is what gives the rank its outsized place in the public imagination.

The masculine form is duke and the feminine duchess. A duchess may hold the dignity in her own right, though this is uncommon, or hold the style as the wife of a duke, which is the usual case. A duchess by marriage does not exercise the dignity independently of her husband, and a widowed duchess conventionally becomes the Dowager Duchess of the place, or uses her forename before the title, when a successor's wife takes the plain style.

Duke derives from the Latin dux, a leader or commander, by way of Old French. It entered English usage as a peerage rank in the fourteenth century, later than the earldom, which is the oldest of the English degrees. From the outset the dukedom was closely associated with the royal house, and for long periods it was conferred principally on the sovereign's sons and closest kin.

The rank's history is not a smooth line of continuity. Dukedoms have been forfeited, extinguished for want of an heir, and revived; the total number in existence has risen and fallen considerably across the centuries. Readers who want the precise standing of a particular dukedom today should consult the Roll of the Peerage maintained by the College of Arms rather than rely on general accounts, including this one.

A royal dukedom is a dukedom held by a member of the Royal Family. The distinction matters in practice because royal dukes are treated according to royal, not peerage, convention: they are approached as members of the Royal Family first and as holders of a peerage second, and the etiquette differs accordingly.

A non-royal duke, sometimes called a duke of the peerage, holds the same rank in the hierarchy but none of the royal connection. Confusing the two is one of the most common errors in writing about the British nobility, and it is worth checking which kind of dukedom is in question before describing a person's standing.

The House of Lords (Hereditary Peers) Act 2026 received Royal Assent on 18 March 2026, and on the end of the 2024–26 session on 29 April 2026 hereditary peers ceased to sit or vote in the House of Lords by virtue of a hereditary peerage. The House now comprises life peers together with the Lords Spiritual, who sit as bishops of the Church of England and are not peers. The titles themselves were not abolished: a duke remains a duke and a baroness remains a baroness, and the ranks, their forms of address and their place in the order of precedence continue exactly as before. What changed is the constitutional consequence of holding a hereditary peerage, not the dignity itself.

For a duke specifically, this means the rank retains its full ceremonial and social meaning and its place at the head of the peerage, while conferring no seat in the legislature by inheritance. A duke may of course sit in the House of Lords for an entirely separate reason — as a life peer, if a life peerage has been conferred — but that is a distinct dignity and not a consequence of the dukedom.

A title of honour is a dignity, not a deed. Holding a peerage does not by itself prove ownership of land, a house or an estate, does not confer public office or any governmental authority, and does not make its holder a representative of the Crown. The territorial word in a title — 'of Somewhere' — is a designation attached to the dignity, and in many modern creations it records a connection rather than a possession.

Almost all dukedoms are hereditary, descending under the terms of the original grant, most commonly to heirs male of the body. Life peerages, created under the Life Peerages Act 1958, are conferred at the rank of baron and baroness only; there is no modern practice of creating life dukedoms. Anyone described as having been 'made a duke for life' has almost certainly been described inaccurately.

This page explains what the rank is. The separate Brattleby guide to addressing a duke covers the practical etiquette in full: the use of Your Grace on formal first address, the ordinary conversational form, the correct opening of a letter, the envelope form, and the different treatment required for a royal duke. The two subjects are kept apart deliberately so that neither page repeats the other.