Viscount Clifden, of Gowran in the County of Kilkenny, Ireland, was a title in the Peerage of Ireland. It was created on 12 January 1781 for James Agar, 1st Baron Clifden. He had already been created Baron Clifden, of Gowran in the County of Kilkenny, in 1776, also in the Peerage of Ireland. The Viscounts also held the titles of Baron Mendip in the Peerage of Great Britain from 1802 to 1974 and Baron Dover from 1836 to 1899, when this title became extinct, and Baron Robartes from 1899 to 1974, when this title became extinct, the two latter titles which were in the Peerage of the United Kingdom. The interrelated histories of the peerages follow below.

The Peerage of Ireland consists of those titles of nobility created by the English monarchs in their capacity as Lord or King of Ireland, or later by monarchs of the United Kingdom of Great Britain and Ireland. It is one of the five divisions of Peerages in the United Kingdom. The creation of such titles came to an end in the 19th century. The ranks of the Irish peerage are duke, marquess, earl, viscount and baron. As of 2016, there were 135 titles in the Peerage of Ireland extant: two dukedoms, ten marquessates, 43 earldoms, 28 viscountcies, and 52 baronies. However, these titles have no official recognition in the Republic of Ireland, with Article 40.2 of the Constitution of Ireland forbidding the state conferring titles of nobility and stating that an Irish citizen may not accept titles of nobility or honour except with the prior approval of the Irish government.