Nicholas Power Richard Le Poer Trench, 9th Earl of Clancarty, 8th Marquess of Heusden (born 1 May 1952), is an Anglo-Irish hereditary peer, as well as a nobleman in the Dutch nobility.

He took his seat in the House of Lords at this time as Viscount Clancarty, a title in the Peerage of the United Kingdom, because titles in the Peerage of Ireland did not entitle their holders to sit even before the House of Lords Act 1999 removed the majority of hereditary peers.

He was unsuccessful in the election by the Crossbench hereditary peers of 28 of their number to continue to sit after the Act came into force, finishing 37th in a field of 79 candidates.

[1] He was an unsuccessful candidate in four by-elections caused by the deaths of sitting hereditary peers, being runner-up on two occasions.

[4] Other than King Willem-Alexander of the Netherlands, who is also Marquis of Veere and Flushing, Lord Clancarty holds the only extant Dutch marquessate.