per wikipedia:
“Carol of the Bells” (also known as the “Ukrainian Bell Carol“) is a popular Christmas carol, with music by Ukrainian composer Mykola Dmytrovych Leontovych in 1914 and lyrics by Peter J. Wilhousky. The song is based on the Ukrainian folk chant “Shchedryk.” Wilhousky’s lyrics are under copyright protection (owned by Carl Fischer Music); the music is in the public domain.

The music is based on a four-note ostinato. It has been performed in many genres: classical, metal, jazz, country music, rock, and pop. The piece has also been featured in films, television shows, and parodies.

Conductor of the Ukrainian Republic Choir Oleksander Koshyts (also spelled Alexander Koshetz) commissioned Leontovych to create the song based on traditional Ukrainian folk chants, and the resulting new work for choir, “Shchedryk”, was based on four notes Leontovych found in an anthology.

The original folk story related in the song was associated with the coming New Year, which, in pre-Christian Ukraine, was celebrated with the coming of spring in April. The original Ukrainian title translates to “the generous one” or is perhaps derived from the Ukrainian word for bountiful (shchedryj), and tells a tale of a swallow flying into a household to proclaim the bountiful year that the family will have.

With the introduction of Christianity to Ukraine and the adoption of the Julian calendar, the celebration of the New Year was moved from April to January, and the holiday with which the chant was originally associated became Malanka (Ukrainian: Щедрий вечір Shchedry vechir), the eve of the Julian New Year (the night of January 13–14 in the Gregorian calendar). The songs sung for this celebration are known as Shchedrivky.

The song was first performed by students at Kiev University in December 1916, but the song lost popularity in Ukraine shortly after the Soviet Union took hold. It was introduced to Western audiences by the Ukrainian National Chorus during its 1919 concert tour of Europe and the Americas, where it premiered in the United States on October 5, 1921 to a sold-out audience at Carnegie Hall. The original work was intended to be sung a cappella by mixed four-voice choir. Two other settings of the composition were also created by Leontovych: one for women’s choir (unaccompanied) and another for children’s choir with piano accompaniment. These are rarely performed or recorded.

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.

One seems to hear
Words of good cheer
From everywhere
Filling the air.

Oh how they pound,
Raising the sound,
O’er hill and dale,
Telling their tale.

Gaily they ring
While people sing
Songs of good cheer,
Christmas is here.

Merry, Merry, Merry, Merry Christmas,
Merry, Merry, Merry, Merry Christmas.

On on they send,
On without end,
Their joyful tone
To every home.

Ding dong ding dong
Ding dong ding dong

Hark how the bells,
Sweet silver bells,
All seem to say,
Throw cares away
(We will throw cares away)

Christmas is here,
Bringing good cheer,
To young and old,
Meek and the bold.
(Bringing cheer to the young and old)

Oh how they pound,
Raising the sound,
O’er hill and dale,
Telling their tale.

Gaily they ring
While people sing
Songs of good cheer,
Christmas is here.

Merry, Merry, Merry, Merry Christmas,
Merry Christmas
Merry, Merry, Merry, Merry Christmas,
Merry Christmas

On on they send,
On without end,
Their joyful tone
To every home.