Who knew it? President Wilson knew it. Colonel House knew it. Other's knew it. Did I know it? I had a pretty good idea of what was going on: I was liaison to Henry Morgenthau, Sr., in the 1912 campaign when President Wilson was elected, and there was talk around the office there.
His opinion that there was a secret deal that resulted in the US entering the First World War on the side of the English. - Willard Hotel speech (1961)