I learned this song in French III at Thomas Jefferson High School in 1965-1966 from Mr. Adair McConnell, who played it on an autoharp.
Diane Taraz sings “Un Flambeau, Jeanette, Isabella.” From Wikipedia:
“Bring a Torch, Jeanette, Isabella” (French: Un flambeau, Jeannette, Isabelle) is a Christmas carol which originated from the Provence region of France in the 17th century. The song is usually notated in 3/8 time.
The carol was first published in France, and was subsequently translated into English in the 18th century. The song was originally not meant to be sung at Christmas; it was considered dance music for French nobility.
It seems likely that the melody was written by Charpentier, derived from the air à boire Qu’ils sont doux, bouteille jolie from the now lost Le médecin malgré lui.
The song title refers to two female farmhands who have found the baby and his mother in a stable. Excited by this discovery, they run to a nearby village to tell the inhabitants, who rush to see the new arrivals. Visitors to the stable are urged to keep their voices quiet, so the newborn can enjoy his dreams.
To this day, on Christmas Eve in the Provence region, children dressed as shepherds and milkmaids carry torches and candles while singing the carol, on their way to Midnight Mass.