I must confess I have added the following discussion to another website but hope you also find it interesting.
La Folia (pronounced lah foh-LEE-ah) which literally means madness, folly or empty-headedness is possibly one of the most remarkable phenomena in musical history. This simple but intriguing tune was first published in 1672 with roots going back to the 16th century. It has been a major challenge for many composers up to the present day, ranging from being part of a Bach Cantata to being incorporated into a film theme by Vangelis. Perhaps the most striking feature is that the theme is not better known despite more than 150 composers making variations of it over a span of nearly 350 years.
It strikes me that this would be an excellent basis for a competition among our members - just out of interest...sadly no cash prizes. Because sometimes I see myself fitting neatly into the meaning of 'La Folia' I have had a crack at writing 12 variations for horn quartet. For your interest the theme proper makes its first entrance in the 1st horn part in variation 5 - it is only 8 notes long.
Incidentally, I have become fixated with this so am now attempting a set of jazz variations - crazy or what!
Comments that might lead to improvements are welcome as always.