[4] Warburg was an important leader of the American Jewish Joint Distribution Committee, established to help the Jews in Europe in the period leading up to, and especially during, the Great Depression.

Warburg actively raised funds in the United States on behalf of European Jews who faced hunger following World War I.

[6][7][8] Warburg and the Joint Distribution Committee were also instrumental in the 1930s after the global Great Depression following the crash of the New York Stock Exchange in 1929.

[9][10] More interested in his charitable work than banking, after Hitler seized power, Warburg gave money to help aid Jews fleeing Germany.

[11] John L. Spivak claimed General Smedley Butler had named Warburg before Congress as part of the Business Plot.