Question: Who was a famous leader of the IRA who fought against the group that helped the RIC during the Irish War of Independence? 

Context paragraphs:
Protestant Action Group: The Protestant Action Group or Loyalist Action Group was a secret loyalist vigilante group active in County Cork during the Irish War of Independence.  It was made up of local Protestant unionists who opposed Irish republicanism.  The group helped British forces by gathering intelligence on the Irish Republican Army (IRA) and local republicans.  It is also alleged to have been involved in the killing of several republicans, most notably the Coffey brothers, who were shot in their home in Enniskean in February 1921.  That year, the IRA found intelligence documents belonging to the British Auxiliary Division in Dunmanway, which apparently confirmed the existence of the group, and included a list of names of informers.  This resulted in many informers being granted safe passage and protection in England by the British government.  During the conflict, the local IRA brigade executed 15 informers, six of whom were Protestants.  In April 1922, after a truce had come into effect, IRA members shot dead 13 Protestants in the Dunmanway area.  It was claimed they were members of the Action Group, but this is disputed.

Kilmeena ambush: The Kilmeena ambush was an action during the Irish War of Independence that took place at Kilmeena, County Mayo on 19 May 1921.  The ambush ended in defeat for the local West Mayo Irish Republican Army (IRA), with six IRA volunteers killed and seven wounded.  Two members of the Royal Irish Constabulary (RIC) and one Black and Tan were also killed in the action.

Liam Pilkington: Liam Pilkington (2 June 1894 – 26 March 1977), also known as William Pilkington and Billy Pilkington, served in the Irish Republican Army (IRA) during the Irish War of Independence.  Pilkington served the IRA as General Officer Commanding (GOC) of the 3rd Western Division IRA from 1921 to 1923.  After the conclusion of the Irish War of Independence Pilkington joined the Anti-Treaty IRA during the Irish Civil War.  He attempted to become a politician for a short while, but was ultimately unsuccessful.  Disillusioned due to the Irish Civil War, Pilkington became a Catholic priest for the remainder of his life.  He served as a priest in South Africa and Wales before retiring to Liverpool, England, where he died.

Auxiliary Division: The Auxiliary Division of the Royal Irish Constabulary (ADRIC), generally known as the Auxiliaries or Auxies, was a paramilitary unit of the Royal Irish Constabulary (RIC) during the Irish War of Independence.  It was set up in July 1920 and made up of former British Army officers, most of whom came from Great Britain.  Its role was to conduct counter-insurgency operations against the Irish Republican Army (IRA).  The Auxiliaries became infamous for their reprisals on civilians and civilian property in revenge for IRA actions, the most well-known example of which was the burning of Cork city in December 1920.

Black and Tans: The Black and Tans (Irish: "Dúchrónaigh" ), officially the Royal Irish Constabulary Special Reserve, was a force of Temporary Constables recruited to assist the Royal Irish Constabulary (RIC) during the Irish War of Independence.  The force was the brainchild of Winston Churchill, then British Secretary of State for War.  Recruitment began in Great Britain in late 1919.  Thousands, many of them British Army veterans of World War I, answered the British government's call for recruits.  Most of the recruits came from Britain, although it also had some members from Ireland.  Their role was to help the RIC maintain control and fight the Irish Republican Army (IRA), the army of the Irish Republic.  The nickname "Black and Tans" arose from the colours of the improvised uniforms they initially wore, composed of mixed khaki British Army and rifle green RIC uniform parts.  The Black and Tans became infamous for their attacks on civilians and civilian property.

Rescue at Knocklong: In one of the most dramatic events in the Irish War of Independence, a handcuffed young Tipperary volunteer, Seán Hogan, was rescued from a train while sat between four armed members of the Royal Irish Constabulary (RIC).  Two RIC were killed in the attack and a number of the volunteers wounded.  The rescue was undertaken by three of Hogan’s comrades from the Third Tipperary Brigade of the IRA and five members of the Galtee Battalion of the East Limerick Brigade.  Hogan was one of the most wanted men in Ireland at the time of his rescue, due to his role in the Soloheadbeg ambush and would almost certainly had been executed if he hadn’t been rescued.  The rescue took place on Hogan’s 18th birthday, 13 May 1919, while the Cork bound train stopped at Knocklong station in Limerick.

Patrick Giles: Patrick Giles (1899 – 13 March 1965) was an Irish Fine Gael politician.  He was born in 1899 on a family farm outside Longwood village in County Meath.  During the Irish War of Independence he was a member of the Irish Republican Brotherhood (IRB), and was captain of the local Longwood Company.  In 1920 he and some of his brothers took part in a raid on the Royal Irish Constabulary (RIC) Barracks in Trim, which was burnt to the ground.  The aim of the raid was to supply arms to local volunteers.  After the raid the arms were dispersed to different sites, one of which was the Giles family farm.  During a raid by the Crown forces, his name was found on a note linking him to the storing of these arms and he was sent to prison in Perth, Scotland for three years, but he got out after one year shortly before the Anglo-Irish Truce.  In the split that followed after the Anglo-Irish Treaty, he, like most of the IRA in County Meath took the Pro-treaty side.  Later he served in the National Army and achieved the rank of Captain.

Frank Carty: Francis Joseph "Frank" Carty (3 April 1897 – 10 September 1942) was a leader of the Irish Republican Army (IRA) in the fight with the Black and Tans in the Irish War of Independence, and a long-serving Fianna Fáil Teachta Dála (TD).

Eoin O'Duffy: Eoin O'Duffy (Irish: "Eoin Ó Dubhthaigh" ; 30 October 1892 – 30 November 1944) was an Irish political activist, soldier and police commissioner.  O'Duffy was the leader of the Monaghan Brigade of the Irish Republican Army (IRA) during the Irish War of Independence and in this capacity became Chief of Staff of the IRA in 1922.  He was one of the Irish activists who along with Michael Collins accepted the Anglo-Irish Treaty and fought as a general in the Irish Civil War on the pro-Treaty side.

Irish Republican Army (1922–69): The original Irish Republican Army (IRA) fought a guerrilla war against British rule in Ireland in the Irish War of Independence between 1919 and 1921.  Following the signing of the Anglo-Irish Treaty on 6 December 1921, the IRA in the 26 counties that were to become the Irish Free State split between supporters and opponents of the Treaty.  The anti-Treatyites, sometimes referred to by Free State forces as Irregulars, continued to use the name Irish Republican Army (IRA) or in Irish Óglaigh na hÉireann, as did the organisation in Northern Ireland which originally supported the pro-Treaty side (if not the Treaty). " Óglaigh na hÉireann" was also adopted as the name of the pro-Treaty National Army, and remains the official legal title of the Irish Defence Forces.  This article deals with the anti-Treaty IRA that fought against the Irish Free State in the Irish Civil War, and with its successors up to 1969, when the IRA split again.

Supporting paragraphs: Frank Carty Black and Tans
Answer: Francis Joseph "Frank" Carty