Jayne Mansfield was a Satanist if I remember correctly.
Her personal life was a mess, even by Hollywood standards. She also had an interest in the supernatural. A year or so before her death she became acquainted with the well known huckster Anton Levay. How far that acquaintance went is still hotly debated. Levay (not exactly a reliable source for anything) claimed she was a Satanist and member of his cult. Most of her friends said Levay was a liar and while she may have attended something once or twice out of curiosity, that it went no further.
I don’t think she was a Christian in any sense most FReepers would acknowledge, but beyond that I doubt anyone really knows. Kyrie eleison.