Stynes was born in Newbridge, County Kildare and attended Newbridge College, where he first played Gaelic football and hurling. He moved to Dublin after World War I to find work. He was sworn into the IRA in 1920 by Sean Lemass, joining "C" Company, 2nd battalion, Dublin brigade. He was stewarding in Croke Park on Bloody Sunday 1920, while carrying concealed guns for the IRA. When British security forces raided the ground, he dumped the guns and escaped over a wall.
Stynes played Gaelic football for the McCracken's club on the Northside, then transferred to the elite O'Tooles club in February 1922. He was an 'outstanding' forward with 'rare qualities'. He took the anti-Treaty side during the Irish Civil War, but managed to play several games for the Dublin senior football team while "on the run" from the Irish Free State authorities. However, he missed Dublin's win in the 1922 All-Ireland final (played 7 October 1923) as by then he was interned in the Curragh Camp. Major General Tom Ennis of the National Army, a former teammate of Stynes who took the pro-Treaty side, secured Stynes' availability for subsequent Dublin matches, and he got a winner's medal for the 1923 final (played 28 September 1924), in which he scored the final two points. He missed the 1924 final (played 26 April 1925) after being suspended by the GAA for breaching its ban on playing "foreign" games by playing soccer, a game he had learnt while in the Curragh.
While suspended from the GAA, he played soccer for Bohemians, where he scored 13 times in 28 appearances during the 1925–26 season. In the Leinster Senior Cup final of 1926, he played well, but retired injured, as Bohs beat Shelbourne 2–1. He also played semi-professionally for Shelbourne at a time when work was hard to find, partly because of his unpopular political views.
In New York
In 1926, Stynes emigrated to the United States, settling in New York City, where he worked as an accountant with Cartier jewellers. He remained active in both North American GAA and emigrant Irish Republican groups. In later years, he returned annually to Ireland for the All Ireland football final in Dublin and political meetings in Northern Ireland.
In May 1927, he played for a New York GAA side that beat the visiting All-Ireland champions, Kerry. He regularly returned to visit Ireland, and represented America in football internationals against Ireland at the Tailteann Games in Dublin in both 1928 and 1932. During his 1928 trip, he turned out once more for Dublin in their Leinster Final defeat to Kildare. He also represented New York touring sides against Mayo in 1932 and Kerry in 1933. In December 1932, he won a Dublin junior club title with Sean McDermotts. He won New York state championships with Kildare in 1938 and with Kilkenny as late as 1947. He also played on the New York hurling teams in 1943 and 1946.
In 1938, Stynes signed on behalf of the American GAA an Irish-American petition for the release of Frank Ryan, the IRA leader imprisoned by Franco's Nationalists during the Spanish Civil War for fighting in the International Brigades. In 1939, he was indicted and charged with attempting to bribe US Customs officials while operating as an agent for the Irish Sweepstakes. He was politically active in Clan na Gael, and after 1948 was leader of the few branches that had remained loyal to the rump of the IRA. In 1949, Stynes supported a decision, which split the Clan, to use its funds for a monument in Dublin to Seán Russell rather than retaining them for a future IRA campaign. After the decline of Clan na Gael, and the outbreak of the Northern Troubles, he was sympathetic to NORAID. He sided with Republican Sinn Féin after its 1986 split from Provisional Sinn Féin, and in 1987 he co-founded the National Irish Freedom Committee (NIFC; Irish: Cumann Na Saoirse Náisiúnta) for its American supporters.
Joe Stynes' brother Peter played Gaelic football for Dublin in the 1925 and 1926 Leinster championships, and got a 1926 League runners-up medal. Peter won Dublin club titles with O'Toole's in 1925, 1926, and 1928. He was the grandfather of Jim Stynes, Australian rules footballer, and his brother Brian, who won an All-Ireland with Dublin in 1995.
- Stynes, Jim; Jim Main (1995). Andrew Ballard, ed. Whatever it Takes. Celebrity Publishing. ISBN 1-875481-40-0.
- Nolan, William; Jim Wren, Marcus de Búrca, David Gorry (2005). The Gaelic Athletic Association in Dublin 1884–2000. Dublin: Geography Publications. ISBN 0-906602-82-3.
- Stynes, p.18
- "Social Security Death Index Search Results". RootsWeb. Ancestry.com. Retrieved 7 October 2009.
- Stynes, p.13
- Nolan, p.194
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- Nolan, p.254
- Stynes, p.14
- "Cumann na Saoirse Naisiunta 2007 Easter Commemoration Report" (PDF). National Irish Freedom Committee. 11 April 2007. Retrieved 25 June 2007.
- Nolan, p.203
- Connolly, Rohan (24 October 2004). "Stynes passion sparks resolve". The Sunday Age. "While in jail, Joe Stynes learnt to play soccer, forbidden for members of the highly politicised Gaelic Athletic Association."
- 'Pivot' (19 April 1926). "Bohemians win final replay". Irish Independent. p. 9.
- Stynes, p.15
- "Kerry's defeat in States: New York team of stars". Irish Independent. 11 June 1927. p. 12.
- "Tailteann International: keen football struggle in prospect". Irish Independent. 17 August 1928. p. 12.
- Nolan, p.263
- Nolan, p.997
- Cronin, Jim. The Kerryman Who Played With Cork. (Interview). Radio Kerry. Retrieved 25 June 2007. "New York at Tralee in 1933 ... had ... Joe Stynes who could kick points from 40 and 50 yards"
- Nolan, p.252
- "Well-known Gaels shine in Kildare's U.S. Win". Irish Independent. 20 December 1938. p. 16.
- Stynes, p.19
- McGarry, Fearghal (1999). Irish Politics and the Spanish Civil War. University College Cork: Cork University Press. p. 105. ISBN 1-85918-239-9.
- "Indicted in Bribery Attempt". New York Times. 20 January 1939. p. 6. Retrieved 31 October 2009.
- Bell, J. Bowyer (1997). The Secret Army: The IRA. Rutgers University: Transaction Publishers. pp. 253–4. ISBN 1-56000-901-2.
- Coogan, Tim Pat (2002). The IRA (2nd ed.). Palgrave Macmillan. p. 277. ISBN 0-312-29416-6. Retrieved 17 April 2009.
- "FOUNDING MEMBERS". National Irish Freedom Committee. Retrieved 25 June 2007.
- White, Robert William (2006). Ruairí Ó Brádaigh: The Life And Politics of an Irish Revolutionary. Indiana Univ. Press. p. 311.
- Bechtel, Mark (29 April 1998). "Spotlight: Getting His Irish Up: Leftfielder Chris Stynes has become the Reds' red-hot spark plug". CNN/SI. Retrieved 25 June 2007. "his grandfather, Joe Stynes, played Irish Rules football"
- Nolan, pp.257–8
- Nolan, pp.1163–4