Dukes | Titles by Rank
- Dukes of Coigny
- Dukes of Coimbra
- Dukes of Concellara
- Dukes of Conegliano
- Dukes of Connaught and Strathearn
- Dukes of Corbara
- Dukes of Corigliano
- Dukes of Cornwall
- Dukes of Courland
- Dukes of Cracóvia
- Dukes of Crequy
- Dukes of Crillon
- Dukes of Croácia
- Dukes of Croy
- Dukes of Croy-Dülmen
- Dukes of Croy-Havre
- Dukes of Croy-S
- Dukes of Cruyllas
- Dukes of Cumberland
- Dukes of Cumberland and Teviotdale
- Dukes of Cumberland e Strathearn
- Dukes of Curlândia e Semgallen
- Dukes of Dalberg
- Dukes of Dalecarlie
- Dukes of Dalmatie
- Dukes of Dato
- Dukes of Denia and Tarifa
- Dukes of Devonshire
- Dukes of Dino
- Dukes of Dmitrov
- Dukes of Dorset
- Dukes of Doudeauville
- Dukes of Douglas
- Dukes of Dover
- Dukes of Duas Pontes
- Dukes of Dunois
- Dukes of Duras
- Dukes of Durazzo
- Dukes of Durcal
- Dukes of Eboli
- Dukes of Edinburgh
- Dukes of Edinburgh
- Dukes of Edinburgh
- Dukes of Eichstadt
- Dukes of Elboeuf
- Dukes of Elchingen
- Dukes of Elio
- Dukes of Elsass
- Dukes of Enghien
- Dukes of Enville