Richard Trench, 2nd Earl of Clancarty
Richard Le Poer Trench, 2nd Earl of Clancarty, 1st Marquess of Heusden (19 May 1767 – 24 November 1837), styled The Honourable from 1797 to 1803 and then Viscount Dunlo to 1805, was an Irish peer, a nobleman in the Dutch nobility, and a diplomat.
He was an Irish, and later British, Member of Parliament and a supporter of Pitt.
Additionally he was appointed Postmaster General of Ireland, and later, of the United Kingdom.
Power Henry Le Poer Trench
Power Henry Le Poer Trench( 11 May 1841 – 30 April 1899) was a British diplomat.
Trench was the son of William Thomas Le Poer Trench, 3rd Earl of Clancarty and Lady Sarah Juliana Butler.
Richard Trench, 4th Earl of Clancarty
Richard Somerset Le Poer Trench, 4th Earl of Clancarty, 3rd Marquess of Heusden (13 January 1834 – 29 May 1891), styled Viscount Dunlo between 1837 and 1872, was an Irish peer, as well a nobleman in the Dutch nobility.
Trench was born in Dublin, Ireland, the son of William Trench, 3rd Earl of Clancarty and Lady Sarah Juliana Butler.
On 29 November 1866 he married Lady Adeliza Georgiana Hervey, daughter of Frederick William Hervey, 2nd Marquess of Bristol and Lady Katherine Isabella Manners.
They had three children.
Donough MacCarty, 1st Earl of Clancarty
Donough MacCarthy, 1st Earl of Clancarty, 2nd Viscount Muskerry( 1594 – 1665), called Donnchadh Mac Cárthaigh in Irish, was a leader of the Irish Confederation.
He led the Confederates' Munster army during most of the Irish Confederate Wars and the Cromwellian conquest of Ireland.
He belonged to the moderate faction, which wanted to collaborate with the royalists against the Commonwealth and the Covenanters.
He was one of the last to surrender.
In 1658, in exile, Charles II created him Earl of Clancarty.
He recovered his lands at the Restoration.
William Le Poer Trench
Colonel The Hon. William Le Poer Trench CVO, JP( 17 June 1837 – 16 September 1920) was an Anglo- Irish politician and British army officer.
He was the third son of William Trench, 3rd Earl of Clancarty and Lady Sarah Juliana Butler.
He married Harriet Maria Georgina Martins, daughter of Sir William Martins, on 21 April 1864.
He fought in the Second Opium War between 1857 and 1858, commanding a ladder company at the capture of Guangzhou and Nankow, and was mentioned in despatches.
He gained the rank of Colonel in the service of the Royal Engineers.
Between 1872 and 1874, he was Member of Parliament( MP) for County Galway, having unseated the elected MP, John Philip Nolan, on petition; the case was one of the most controversial Irish cases of its time and permanently damaged the reputation of the judge, William Keogh.
He held the office of Justice of the Peace for Westminster, London, Buckinghamshire, and Middlesex.
He was made a Commander of the Royal Victorian Order in 1912.
Frederick Trench (British Army officer)
General Sir Frederick William Trench( 17756 December 1859), was a British Army officer and Tory politician.
Charles Le Poer Trench
The son of William Trench, 1st Earl of Clancarty, he was educated at Trinity College, Dublin.
He was appointed Vicar general of the Diocese of Clonfert and Kilmacduagh in 1816.
He was appointed Archdeacon of Ardagh in 1821.
He died in the autumn of 1839.
His brother was the final Archbishop of Tuam.
William Trench, 3rd Earl of Clancarty
William Thomas Le Poer Trench, 3rd Earl of Clancarty, 2nd Marquess of Heusden (21 September 1803 – 26 April 1872), styled Viscount Dunlo between 1805 and 1837, was an Irish peer, as well a nobleman in the Dutch nobility.
He was educated at St John's College, Cambridge.
Trench was born in Castleton, County Kildare, Ireland the son of Richard Trench, 2nd Earl of Clancarty and Henrietta Margaret Staples.
On 8 September 1832, he married Lady Sarah Juliana Butler.
They had six children.
Henry Monck, 1st Earl of Rathdowne
Henry Stanley Monck, 1st Earl of Rathdowne and 2nd Viscount Monck( 26 July 1785 – 20 September 1848), was the son of Charles Monck, 1st Viscount Monck, and Anne Quin.
On 28 July 1806, he married Lady Frances Mary Trench, daughter of William Trench, 1st Earl of Clancarty, and his wife Anne, Countess of Clancarty(" née" Gardiner).
They had 11 daughters.
As he died without male heirs, the earldom became extinct and the viscountcy was inherited by his brother Charles.
John Lindsay, 19th Earl of Crawford
John Lindsay, 19th Earl of Crawford and 3rd Earl of Lindsay( died December 1713) was a Scottish peer and politician.

Question: What nationality is William Trench, 3Rd Earl Of Clancarty's father?