This popular theme of the Christmas season is based on a Ukrainian folk tune, "Shchedryk," which actually has nothing to do with Christmas.  First arranged for voices by Ukrainian composer Mikhail Leontovich, it was later adapted to an English text by Peter Wilhousky and given the Christmas-themed title "Carol of the Bells."  This arrangement looks back to the Ukrainian version for inspiration, realizing the folk theme for percussive timbres.  It is scored for 4 marimbas plus crotales.  A beautiful arrangement!