This is a score for extended symphonic orchestra.
There is an explanation for the title on Youtube. The main theme is a popular tune that appears for the first time in the 12th century. Every new appearance has other lyrics, but the tune is more or less the same. My Pierlala character is situated in the 18th and 19th century. His rebirth has to do with the French occupation of my country and the Brabant Revolution (1830) that ended in the beginning of the new state Belgium.