A video of a monolingual Irish speaker Seán Ó hEinirí (John Henry), who passed away in 1998. You won't see many of these anymore. This video is from a documentary called 'In Search of the Trojan War' from 1985.
Dr. Seamus Ó Cathain from UCD in the video.
Information on the documentary: http://en.wikipedia.org/wiki/In_Search_of_the_Trojan_War
Information on the Irish language: http://en.wikipedia.org/wiki/Irish_language