[2] Organized by Dr. Edward K. Barsky, the American Medical Bureau recruited doctors, dentists, nurses, administrators, ambulance drivers to support the Spanish Loyalists.

[3] In the United States, the AMB also staged events to try to shift public opinion away from supporting the aid boycott to the Spanish Republic, which was imposed by the US government after the Non-intervention Committee's agreements.

Many women leaders in the aid movement were wives of prominent American leftists or of soldiers in the Lincoln Battalion.

Marion Merriman, wife to Abraham Lincoln Battalion Commander Robert Merriman (the supposed inspiration of Ernest Hemingway's hero in For Whom the Bell Tolls), was the chairwoman of the large San Francisco, California, branch of the organization.

Evelyn Hutchins, an active member of the AMB, agitated for years to be a hospital driver on the front liines, but Spanish Republican policies prevented women from serving on there until 1938, when Hutchins won the right to serve on the front line as a driver.