Dukes | Titles by Rank
- Dukes of Harar
- Dukes of Harcourt
- Dukes of Havré
- Dukes of Hereford
- Dukes of Hernani
- Dukes of Herzgovina
- Dukes of Hijar
- Dukes of Hoboken
- Dukes of Hogstraten
- Dukes of Hohenberg
- Dukes of Holstein
- Dukes of Holstein-Gottorp
- Dukes of Hoogstraeten
- Dukes of Hornachuelos
- Dukes of Hornes
- Dukes of Hostun
- Dukes of Huéscar-I
- Dukes of Huéscar-II
- Dukes of Huete
- Dukes of Hungria
- Dukes of Huntington
- Dukes of Illiria
- Dukes of Infantado
- Dukes of Inverness
- Dukes of Ireland
- Dukes of Jägerndorf
- Dukes of Jamnitz
- Dukes of Jelzi
- Dukes of Jerica
- Dukes of Joyeuse
- Dukes of Juliers
- Dukes of Kaluga
- Dukes of Kendal
- Dukes of Kendall
- Dukes of Kent
- Dukes of Kent
- Dukes of Kent and Strathearn
- Dukes of Kien Giang
- Dukes of Kingston-upon-Hull
- Dukes of Kintyre e Lorne
- Dukes of Klewan e Zukow
- Dukes of Kosel
- Dukes of Krumau
- Dukes of Ksani
- Dukes of Kwiawia
- Dukes of la Alcudia
- Dukes of la Conquista-E
- Dukes of la Conquista-I
- Dukes of La Force
- Dukes of La Meilleraye