Creator Alme Siderum (Creator, maker of the stars) is a chant hymn for the First Sunday of Advent. The hymn is based on the 7th century hymn Conditor alme siderum, which underwent heavy revision in 1632 by Pope Urban VIII to fit the meters of classical Latin. Only one line of the original remained in the new version
Creator Alme Siderum is in the Liber Usualis, the book that contains the Gregorian chant for all the Masses of the year as well as the Divine Office. (Please note: not even the Liber Usualis was spared by the progressivists, as it was revised in the '50s and '60s to fit in with liturgical “reforms”.)
The hymn pleads for the Maker of the stars to hear our prayers and to defend us from the enemy with the weapons of heavenly grace.
Creator Alme Siderum is interpreted here by the Czech choir, Schola Gregoriana Pragensis.