Wordorigins.org

Believe it or not, the term United Nationswas actually coined by Franklin Roosevelt and Winston Churchill while the British prime minister was sitting in a bathtub. (Churchill had the habit of thinking and writing while in the tub.) Churchill was in Washington over the New Year’s holiday 1941-42 and the two men were struggling with what to officially call the group of nations that was about to sign the Atlantic Charter. Churchill would write in Volume III of his The Second World War:

The title of “United Nations” was substituted by the President for that of “Associated Powers.” I thought this a great improvement. I showed my friend the lines from Byron’s Childe Harold:

Here, where the sword United Nations drew,
Our countrymen were warring on that day!
And this much—and all—which will not pass away.

The President was wheeled in to me on the morning of January 1. I got out of my bath, and agreed to the draft.

Two days later Churchill would write to his cabinet back in London on 3 January 1942:

You will have got my two telegrams about what we did yesterday. President has chosen the title “United Nations” for all the powers now working together. This is much better than “Alliance,” which places him in constitutional difficulties, or “Associated Powers,” which is flat.

The application of the term to what would become the post-war international organization happened later that year in a speech by Vice President Henry Wallace on 9 November:

When this war comes to an end, the United Nations will have such overwhelming superiority in air power that we shall be able to speedily enforce any mandate whenever the United Nations may have arrived at a judgment based on international law.

The first article in the international law of the future is undoubtedly the United Nations’ Charter. The United Nations’ Charter includes the Atlantic Charter and there is little reason it should longer be called the “Atlantic Charter” in view of the fact that the broader instrument has been validated by thirty nations.

Just as the name United Nations comes from the wartime alliance, so to does the modern organization, which was initially formed by the Allies fighting the war.