Keenan was interned without trial on three occasions: 1940–1945, 1957–1961, and 9 August 1971 – 27 April 1972. He spent a total of 15 years in jail despite never being convicted of an offence. In March 1972, a month before his final release, he was paroled for the funeral of his son Colm, a Provisional Irish Republican Army officer who had been shot by the British Army.
Keenan was chairman of the Derry Citizens Defence Association between July and October 1969, and played a prominent role in the events surrounding the creation and defence of Free Derry. In the late 1980s, he was made honorary vice president for life of Republican Sinn Féin until his death.
He is commemorated annually by Republican Sinn Féin in the month of March at the Seán Keenan Memorial (Celtic Cross) on Fahan Street in the Bogside area of Derry City.
- Derry republican remembered Aeneas Bonner. Retrieved 2008-03-01
- "Legality of detention challenged in London", The Irish Times, 14 September 1971, p. 9
- "Whitelaw frees 22 more internees", The Irish Times, 28 April 1972, p. 5
- What to see and do - Murals and Monuments www.visitderry.com. Retrieved 2009-06-21
- Sean Keenan: Final farewell Roisin McManus. 2006-08-04. Retrieved 2008-02-25
- Seán Keenan Memorial to 60 years of service - Ireland's OWN at the Wayback Machine (archived February 6, 2007)
- Internment, John McGuffin (1973) Chapter 8 - INTERNMENT 1971: THOSE DETAINED
|This Irish biographical article is a stub. You can help Wikipedia by expanding it.|
|This Irish history article is a stub. You can help Wikipedia by expanding it.|