Beginning in the 17th Century, an anonymous dance tune known as “La Folia” captivated countless composers who employed it as a theme for sets of variations. The set that inspired most of the rest was ...

Rachmaninoff's "Variations on a Theme of Corelli," Op. 42, is, in a sense, misnamed. It's based on a tune that Corelli made famous use of, in one of his sonatas, but Corelli didn't come up with it ...