Johannes Daniel Falk

German theologian, author, lyricist, and philanthropist (born October 28, 1768 in Danzig, Prussia, Germany [now Gdansk, Poland] – died February 14, 1826 in Weimar, Thuringia, Germany)

In 1813, Falk established a charity organization in Weimar, the "Gesellschaft der Freunde in der Not" (Association of Friends in Need) that dedicated itself to raising children orphaned by the Napoleonic Wars. In addition to food and shelter, he provided the children with schooling and professional training. His non-violent pedagogy and care for orphans became a model for many other social welfare programs for youth.

Around 1816, Falk wrote the first stanza of "O Du Fröhliche, Oh Du Selige" after a traditional melody shared with him by his friend, Johann Gottfried Herder. Since he imagined the song as a song for all major Christian holidays, he called it "Allerdreifeiertagslied" (i.e., Song for all three Holidays), with a second stanza dedicated to Easter and a third to Pentecost. In 1827, Heinrich Holzschuher wrote two new stanzas and turned the song into what became one of the best-known German Christmas songs.