This episode takes place in Cherbourg, France on June 4, 1944 and in Arizona in 1968.
Michael St. Clair (Duchamps) had earlier guest starred in the WWII-based Anchors Aweigh, Men of Stalag 13 (1965).
John Wengraf (Dr. Hans Kleinemann) was a Jewish actor who fled from Nazi Germany in the 1930s. This 1966 performance was his final credited acting role. He lived in retirement until 1974.
The three Frenchmen (Duchamps, Mirabeau, and Verlaine) have famous names lifted from French art, history, and poetry.