Philip John Noel-Baker was a man of strong and steadfast convictions. To a reporter who interviewed him after the Norwegian Nobel Committee announced that he had been awarded the Peace Prize, he said, "War is a damnable, filthy thing and has destroyed civilization after civilization - that is the essence of my belief."

P.J. Noel-Baker participated in the formation, the administration, and the legislative deliberations of the two great international political organizations of the twentieth century - the League of Nations and the United Nations. In 1918-1919, during the Peace Conference in Paris, he was principal assistant to Lord Robert Cecil on the committee which drafted the League of Nations Covenant; from 1920 to 1922 a member of the Secretariat of the League, being principal assistant to Sir Eric Drummond, first secretary-general of the League; from 1922 to 1924 the private secretary to the British representative on the League's Council and Assembly. Meanwhile, he also was acting as a valued adviser to Fridtjof Nansen in his prisoner-of-war and refugee work. From 1929 to 1931 he was a member of the British delegation to the Assembly of the League and then for a year an assistant to Arthur Henderson, the chairman of the Disarmament Conference.