Duke of Leinster
| Dukedom of Leinster | |
|---|---|
| Argent a saltire gules | |
| Creation date | 26 November 1766 |
| Created by | King George III |
| Peerage | Peerage of Ireland |
| First holder | James FitzGerald, 1st Marquess of Kildare |
| Present holder | Maurice FitzGerald, 9th Duke |
| Heir presumptive | Edward FitzGerald (nephew of the present holder) |
| Remainder to | the 1st Duke's heirs male of the body lawfully begotten |
| Subsidiary titles | Marquess of Kildare Earl of Kildare Earl of Offaly Viscount Leinster Baron of Offaly Baron Offaly Baron Kildare |
| Former seats | Maynooth Castle Kilkea Castle Leinster House Carton House |
Duke of Leinster (/ˈlɪnstər/; Irish: Diúc Laighean) is a title that has been created twice in the Peerage of Ireland since 1691. It does not include any territorial landholdings and does not produce any revenue for the title-holder.
Currently Duke of Leinster is the premier dukedom in the Peerage of Ireland. The subsidiary titles of the Duke of Leinster are Marquess of Kildare (1761), Earl of Kildare (1316), Earl of Offaly (1761), Viscount Leinster, of Taplow in the County of Buckingham (1747), Baron of Offaly (c. 1193), Baron Offaly (1620) and Baron Kildare, of Kildare in the County of Kildare (1870). The viscounty of Leinster is in the Peerage of Great Britain, the barony of Kildare in the Peerage of the United Kingdom, and all other titles in the Peerage of Ireland. The courtesy title of the eldest son and heir of the Duke of Leinster is Marquess of Kildare. The Duke of Leinster is the head of the House of Kildare.