The Romanian Christmas Carols are comprised of original Romanian folk tunes, collected by Bartók over the course of many years, beginning in 1909. While much of his folk-inspired music used peasant dance music as sources, the carols use only vocal music, and as such are very different in character from the dance-tune derived music. The most striking difference is in the flexible rhythms of the carol melodies, as opposed to the fixed rhythms of the peasant dances. There are twenty Romanian Christmas Carols in this work, divided into two sets, each to be played without pause between songs (each song blends into the next). Dutch arranger Andreas van Zoelen arranged the second set of 10 carols for a Symphonic Band.