I have read that "Marlene" Dietrich was originally named Maria Magdelena Dietrich. If this is true, would Marlene then be a contraction of of Maria Magdelena? Or did the name exist before Ms. Dietrich in other contexts for other people?
Born about the same time as Marlene Dietrich was a female film producer who went by the name "Leni." Apparently it was a contraction of the name Helene. Is Leni ONLY a reference to Helene, or can it be used to refer to women named Marlene, Arlene, Darlene, and similar names?