I think the modern art period can be traced back to the 1920s, but anywho, there is also the component of reception. It's not just what the artists says, but if

I think the modern art period can be traced back to the 1920s, but anywho, there is also the component of reception. It's not just what the artists says, but if the Art World receives it as such. Actually it turns out wikipedia traces modern art back to the 1860s.