The emphasis of the artwork, also called the center of interest is the most important part.
Alot of cultural things helped develope jazz especcially in new orleans where i recently was. most of the things that influenced jazz where the spirits of the people, wether sad or happy they always used jazz to show their spirits. but more things than feelings made jazz. you see jazz started around the time the french had gone into luisianna(sorry its spelled wrong) after they did the spanish forced their way into the new state and made everyone obey their rules. even though they followed those rules they still kept almost everything french made and french run but eventually people started mixing the instruments from spain and the instruments from france and learned how harmonic they sounded together eventually songs were made and the era of swing and jazz started not sure if i answered your question the way you wanted but hope this helps
