Decadent movement

Decadence generally refers to a "process, condition, or period of deterioration or decline, as in morals or art; decay" (http://www.thefreedictionary.com).

Sources

http://www.thefreedictionary.com/decadence

http://libcom.org/library/decadence-aufheben-2

http://www.english.uwosh.edu/roth/Decadence.htm