Like ‘O come, O come, Emmanuel’, the ‘Carol of the Bells’ is also written in a minor key and is derived from an ancient melody:

The chant based on an ostinato four-note pattern within the range of a minor third is thought to be of prehistoric origins and was associated with the coming New Year which in Ukraine before the introduction of Christianity was originally celebrated in April.

Once Christianity became established in the Ukraine, this song was sung months earlier, at the time of the Epiphany and the New Year in the Julian calendar: January 13. Ukranian songs sung for this occasion are known as Schedrivky, named after the Epiphany — Shchedry vechir.

The Ukranian title for ‘Carol of the Bells’ is ‘Shchedryk’, which translates as ‘Bountiful Evening’. The original lyrics describe the flight of a swallow into a family home to announce the plentiful New Year the family would have:

Shchedryk, shchedryk, a shchedrivka [New Year’s carol];
A little swallow flew [into the household]
and started to twitter,
to summon the master:
“Come out, come out, O master [of the household],
look at the sheep pen,
there the ewes are nestling
and the lambkin have been born
Your goods [livestock] are great,
you will have a lot of money, [by selling them]

if not money, then chaff: [from all the grain you will harvest]
you have a dark-eyebrowed [beautiful] wife.”
Shchedryk, shchedryk, a shchedrivka,
A little swallow flew.

The song came to the United States in the 1920s, when the Ukranian National Chorus and Ukranian Republic Capella began touring American concert halls.

Peter Wilhousky, an American composer of Ukranian and Russian descent, heard the Ukranian National Chorus sing this song at Carnegie Hall in 1921. In 1936, he wrote the English lyrics we now know (more at the link):

Hark! how the bells
sweet silver bells
All seem to say
throw cares away.

Christmas is here
bringing good cheer
To young and old
meek and the bold

Ding, dong, ding, dong
that is their song,
With joyful ring
all caroling …

This rendition of the carol, sung by the Mormon Tabernacle Choir, is the best I have heard yet. I hope that you enjoy it, too: