According to her autobiography, Leni Riefenstahl by Leni Riefenstahl,
she was a Protestant.
Page 11: Easter Sunday 1918, "I was confirmed at the Kaiser Wilhelm
Page 104: circa 1932, "Monsignor Frings asked me whether I would be
willing to make films for the Catholic Church. As a Protestant I was
absolutely amazed by this offer."
Use the ?search inside? feature for this book on amazon.com with the
search words: religion or protestant.
Leni Riefenstahl by Leni Riefenstahl
I hope this answers your question. If it does not, or the answer is
unclear, then please ask for clarification of this research before
rating the answer. I shall respond to the clarification request as
soon as I receive it.
As described above