Today we feature the chanson, Alma Redemptoris Mater, by Guillaume du Fay. Unlike his other pieces, he uses the form of a galliard in duet with musical accompaniment and breaks from the tradition of the Gregorian chant which he follows closely in other pieces. The 15th century saw many popular tunes used in compositions for sacred librettos. The practice was an attempt to animate the liturgy with secular music, but was condemned and forbidden by the Council of Trent.