Viscount Clermont, of Clermont in the County of Louth, was a title in the Peerage of Ireland. It was created in 1776 for William Fortescue, 1st Baron Clermont, with remainder in default of male issue of his own to his brother James Fortescue and the heirs male of his body. He was the son of Thomas Fortescue. Fortescue had already been made Baron Clermont, of Clermont in the County of Louth, in the Peerage of Ireland in 1770, with normal remainder to heirs male, and was made Baron Clermont, of Clermont in the County of Louth, in the Peerage of Ireland at the same time as he was granted the viscountcy, also with remainder to his brother James Fortescue. In 1777 he was further honoured when he was made Earl of Clermont, in the County of Louth, in the Peerage of Ireland, with normal remainder to heirs male. Lord Clermont died without male issue in 1806 when the barony of 1770 and earldom became extinct. He was succeeded in the barony of 1776 and viscountcy according to the special remainder by his nephew William Fortescue, the second Viscount, the son of the aforementioned James Fortescue. The second Viscount Clermont represented County Louth in both the Irish and British Parliaments and was an Irish Representative Peer. He died unmarried in 1829 when the barony and viscountcy became extinct.
The Clermont title was revived in 1852 when Thomas Fortescue was made Baron Clermont. He was a descendant of Chichester Fortescue, brother of William Fortescue, grandfather of the first Earl of Clermont.
Viscounts Clermont (1776)
- William Henry Fortescue, 1st Viscount Clermont (1722–1806) (created Earl of Clermont in 1777)
Earls of Clermont (1777)
- William Henry Fortescue, 1st Earl of Clermont (1722–1806)
Viscounts Clermont (1776; Reverted)
- William Charles Fortescue, 2nd Viscount Clermont (1764–1829)
In 1701, Charles Middleton, previously 2nd Earl of Middleton was awarded the Jacobite peerages of Earl of Monmouth and Viscount Clermont in the Peerage of England. The titles, such as they were, became extinct on the death of his son in 1747.