Jeska Vardinski, Enough Said

When exactly did Cher start going by one name?  Does anyone know the date, the occurrence, why it happened?  Did she just wake up one day and say, damn, it is too much of a hassle and people know me far too well to mess with anything else.  I want my name to be Cher.  I wonder if Prince did the same thing.  The dude didn't even need a name.  Holy crap, I am having a flashback.  Have I written this blog post before?  Anyway, Jeska Vardinski might not be that far behind.  Do I exaggerate you...