Who was a famous leader of the IRA who fought against the group that helped the RIC during the Irish War of Independence? 
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). 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.
Francis Joseph "Frank" Carty