| Earldom of Rosse | |
| Creation Date: | 3 February 1806 |
| Creation: | Second |
| Peerage: | Peerage of Ireland |
| First Holder: | Laurence Parsons, 1st Viscount Oxmantown |
| Present Holder: | Brendan Parsons, 7th Earl of Rosse |
| Heir Apparent: | Lawrence Parsons, Lord Oxmantown |
| Subsidiary Titles: | Baron Oxmantown |
| Status: | Extant |
| Motto: | PRO DEO ET PATRIA AD ASTRA ("For god and country to the stars") |
| Earldom of Rosse | |
| Creation Date: | 16 June 1718 |
| Creation: | First |
| Peerage: | Peerage of Ireland |
| First Holder: | Laurence Parsons, 2nd Viscount Rosse |
| Last Holder: | Richard Parsons, 2nd Earl of Rosse |
| Subsidiary Titles: | Viscount Rosse Baron Oxmantown |
| Status: | Extinct |
| Extinction Date: | 17 August 1764 |
| Motto: | PRO DEO ET REGE ("For God and the King") |
Earl of Rosse is a title that has been created twice in the Peerage of Ireland, both times for the Parsons family. "Rosse" refers to New Ross in County Wexford.
The Parsons were originally an English family from Dishworth (Diseworth) Grange in Leicestershire; there having been five brothers who settled in Ireland during the late 16th century. One of the brothers, William Parsons, was created a Baronet in the Baronetage of Ireland of Bellamont in the County of Dublin in 1620 by James VI & I.[1] The third Baronet was created Viscount Rosse in the Peerage of Ireland in 1681, and the second Viscount was created Earl of Rosse in the Peerage of Ireland in 1718; these titles of the first creation became extinct on the death of the second Earl in 1764.
Sir Lawrence Parsons, the younger brother of Sir William Parsons, 1st Baronet, settled in Birr, King's County, later known as Parsonstown, and was the ancestor of the younger (Birr) branch of the family. His grandson Laurence Parsons was created a Baronet, of Birr Castle in King's County, in the Baronetage of Ireland in 1677, but was attainted by King James II's Parliament in 1689 and sentenced to death. The sentence was never carried out, however. His great-grandson, the third Baronet, and great-great-grandson, the fourth Baronet, both represented King's County in the Irish House of Commons. The latter's half-brother Laurence Harman Parsons was in 1792 raised to the Peerage of Ireland as Baron Oxmantown, with remainder to his nephew Sir Lawrence Parsons, 5th Baronet, who had succeeded his father the fourth Baronet in 1791.
In 1795 he was made Viscount Oxmantown in the Peerage of Ireland, with normal remainder to the heirs male of his body, and in 1806 he was even further honoured when he was created Earl of Rosse in the Peerage of Ireland, with similar remainder as for the barony. Lord Rosse sat from 1800 to 1807 as one of the original Irish representative peer in the British House of Lords. On his death in 1807 the viscountcy became extinct while he was succeeded in the barony and earldom according to the special remainders by his aforementioned nephew, the 5th Baronet. The latter represented King's County in the British House of Commons and sat in the House of Lords as an Irish Representative Peer between 1809 and 1841.
The 2nd Earl's son, the 3rd Earl, was a well-known astronomer and famous for his construction of the giant telescope the Leviathan of Parsonstown at his seat Birr Castle.[2] Lord Rosse also sat as Member of Parliament for King's County, was an Irish Representative Peer from 1845 to 1867 – years during which millions of the Irish population died from starvation or emigrated. He was one of the very few who foresaw the consequences of the potato blight and tried to alert the British authorities. He was Lord Lieutenant of King's County from 1831 to 1867 and President of the Royal Society from 1849 to 1854. He was succeeded by his son, the fourth Earl. He was an Irish Representative Peer between 1868 and 1908 and Lord Lieutenant of King's County between 1892 and 1908. His son, the fifth Earl, was an Irish Representative Peer from 1911 to 1918 and Lord-Lieutenant of King's County from 1908 to 1918. Lord Rosse fought in the First World War and died from wounds received in action in 1918. the titles are held by his grandson, the seventh Earl, who succeeded his father in 1979.
When the present Earl worked for the United Nations Development Programme, he did not use his title, preferring to be known by his family surname of Parsons.
The family seat is Birr Castle, near Birr, County Offaly.
The heir apparent is the present holder's son, Lawrence Patrick Parsons, Lord Oxmantown (born 1969).
The heir apparent's heir apparent is his son, the Hon. William Charles Yufan Parsons (born 2008).