I noticed a few weeks ago that one of my favorite songs in the LDS Children’s Songbook is actually a Silesian folk song. According to the songbook, the words are supposedly from the 12th century by an anonymous composer, though this blog says, “it is better to associate the hymn with followers of John Hus,” which would put it more in the 15th century.
Either way, it is a beautiful hymn, and my ancestors are Silesian.
Here is the Mormon Tabernacle Choir performing it.