Robert Erskine Childers, the author of the Riddle of the Sands and former Clerk of the British House of Commons served as one of the secretaries of the Irish delegation. Tom Jones was one of Lloyd George's principal assistants, and described the negotiations in his book Whitehall Diary. Notably, the Irish President Éamon de Valera did not attend.
Winston Churchill had a dual role in the British cabinet concerning the Treaty. Firstly as Secretary for War hoping to end the Irish War of Independence in 1921; then in 1922 as Secretary for the Colonies (which included Dominion affairs) he was charged with implementing it.