As the NSDAP consolidated its power, several disputes arose between Hanfstaengl and Germany’s Propaganda Minister, Joseph Goebbels. Hanfstaengl was removed from Hitler’s staff in 1933. He and Helene divorced in 1936. Hanfstaengl fell completely out of Hitler’s favour after he was denounced by Unity Mitford, a close friend of both the Hanfstaengls and Hitler.
In 1937, Hanfstaengl received orders to parachute into an area held by the nationalist side of the Spanish Civil War, to assist in negotiations. While on board the plane he feared a plot on his life and learned more details from the pilot about the mission, who eventually admitted he had been ordered to drop Hanfstaengl over republican-held territory, which would have meant almost certain death. The pilot eventually landed on a small airfield after claiming an engine malfunction following a brief talk with Hanfstaengl, which allowed him to escape.
This version of the story was related by Albert Speer in his memoirs, who stated that the “mission” to Spain was an elaborate practical joke, concocted by Hitler and Goebbels, designed to punish Hanfstaengl after he’d displeased the Führer by making “adverse comments about the fighting spirit of the German soldiers in combat” in the Spanish Civil War. Hanfstaengl was issued sealed orders from Hitler which were not to be opened until his plane was in flight. These orders detailed that he was to be dropped in “Red Spanish territory” to work as an agent for Francisco Franco. The plane, according to Speer, was merely circling over Germany containing an increasingly disconcerted Hanfstaengl, with false location reports being given to convey the impression that the plane was drawing ever closer to Spain. After the joke had played itself out, the pilot declared he had to make an emergency landing and landed safely at Leipzig Airport. Hanfstaengl was so alarmed by the event that he defected soon afterward.
In a late 1960s interview at his home in Schwabing (Munich), Hanfstaengl said he was convinced he was to be tossed out of the plane sans parachute over northern Germany.
He made his way to Switzerland and after securing his son Egon’s release from Germany, he moved to England where he was imprisoned as an enemy alien after the outbreak of World War II. He was later moved to a prison camp in Canada. In 1942, Hanfstaengl was turned over to the U.S. and worked for President Roosevelt’s “S-Project”, revealing information on approximately 400 Nazi leaders. He provided 68 pages of information on Hitler alone, including personal details of Hitler’s private life, and he helped Professor Henry Murray, the Director of the Harvard Psychological Clinic, and psychoanalyst Walter C. Langer and other experts to create a report for the OSS, in 1943, designated the “Analysis of the Personality of Adolph Hitler”. In 1944, Hanfstaengl was handed back to the British, who repatriated him to Germany at the end of the war. William Shirer, a CBS journalist who resided in Nazi Germany until 1940 and was in frequent contact with Hanfstaengl, described him as an “eccentric, gangling man, whose sardonic wit somewhat compensated for his shallow mind.”
Hanfstaengl wrote Unheard Witness (1957) (later re-released as Hitler: The Missing Years) about his experiences. In 1974, Hanfstaengl attended his 65th Harvard Reunion, where he regaled the Harvard University Band about the authors of various Harvard fight songs. His relationship to Hitler went unmentioned.
Hanfstaengl died in Munich in 1975. In 2004, his story was told by author Peter Conradi in his book Hitler’s Piano Player: The Rise and Fall of Ernst Hanfstaengl, Confidante of Hitler, Ally of FDR.