"Fin de siecle" refers specifically to the ending of one of these time periods
The phrase 
usually refers specifically to the end of the nineteenth century,... [DOC] [TLE] Popular tenor Bastian sings change of eras music [PAR] "Fin de Siecle" refers to the closing of one era and the beginning of a new one, 
more specifically to the end of the 19th century, thought to be a period of decline, 
but ... "The end of an era can be a time of great transition, as some challenge the 
previous ... melodic and harmonic concepts without breaking them," Bastian said.