Sir William Parsons, 2nd Baronet of Bellamont, was the only son of Sir Richard Parsons, and his first wife Lettice Loftus. He married Catherine, the eldest daughter of Lord Arthur, Viscount of Ranelagh. Sir William became the 2nd Baronet of Bellamont when his grandfather, Sir William Parsons, died in 1650. His son, Sir Richard Parsons, succeeded him as 3rd Baronet of Bellamont upon his death in 1658.
Lord Richard Parsons, 2nd Earl of Rosse, was born around the year 1716 to Lord Richard Parsons, 1st Earl of Rosse, 2nd Viscount Rosse, Baron of Oxmantown, and his wife Lady Mary Paulet. He succeeded his father in 1741 as the 2nd Earl of Rosse. Lord Richard Parsons died on 27 August 1764 with no children, ending the line of the Parsons of Bellamont. Representation of the family then fell to Sir William Parsons, 4th Baronet of Birr Castle.
Sir Laurence Parsons, 1st Baronet of Birr Castle, was the eldest son of William Parsons Esquire of Birr. He was created baronet on 15 December 1677. Sir Laurence married Lady Frances Savage of Rheban, county Kildare. He died in 1698 and was succeeded by his only son, Sir William Parsons.
Sir William Parsons, 4th Baronet of Birr Castle, was born on 6 May 1731 to Sir Laurence Parsons, 3rd Baronet of Birr Castle, and Lady Mary Sprigge. He succeeded his father as the 4th Baronet of Birr Castle in 1749. In 1764 He became the head of the Parsons family upon the death of Richard Parsons, 2nd Earl of Rosse (of the first creation). Sir William Parsons die on 1 May 1791, and was succeeded in the baronetcy by his son, Sir Laurence Parsons.
Lord Laurence Parsons, 1st Earl of Rosse, Viscount of Oxmantown, Baron of Oxmantown, was born 26 July 1742 to Sir Laurence Parsons, 3rd Baronet of Birr, and Lady Anne Harman. As a second son he did not inherit the baronetcy, which instead passed to his half-brother William, in 1749. He married Lady Jane, the eldest daughter of Lord Edward, 1st Earl of Kingston, and they had one daughter, Frances. On 25 September 1792 he was elevated to the peerage as Baron of Oxmantown, a title which would pass on to his nephew, William’s Son, Sir Laurence Parsons. On 6 October 1795 he was elevated to the peerage again, and given the Viscounty of Oxmantown. In February 1806, he was created the Earl of Rosse. On the 20th April 1807, Lord Laurence died without any sons, his viscounty expired, but the title of Earl of Rosse was passed on to Sir Laurence, 5th Baronet of Birr Castle.
Laurence Michael Harvey Parsons, 6th Earl of Rosse, Baron of Oxmantown, 9th Baronet of Birr Castle, was born 28 September 1906 to Lord William Edward Parsons, 5th Earl of Rosse, and Lady Francis Lois Lister-Kaye. He was educated at Eton College and Christ Church, Oxford, where he was a member of the Railway Club. Laurence Parsons succeeded his father in 1918 as the 6th Earl of Rosse. On 19 September 1935, he married Lady Anne Messel, daughter of Lieutenant-Colonel Leonard Charles Rudolph Messel. Lady Anne Messel was previously married to Ronald Armstrong-Jones, and was the mother of Antony Armstrong-Jones, 1st Earl of Snowdon, who in 1960 married the Princess Margaret, sister of Queen Elizabeth II of the United Kingdom. The 6th Earl of Rosse died on 5 July 1979 and was succeeded by his son, Sir William Brendan Parsons.
Superior of Irish Mission: 30 September 1812-28 September 1817; 29 September 1821- May 1830
Vice Provincial: 1834-1836