Plainsong

Plainsong, or plainchant, is the unaccompanied monophonic chant of the medieval Western Church: a single melodic line, sung in Latin to the texts of the Mass and the Divine Office, moving in free rhythm according to the words. Its largest body is Gregorian chant, codified in Carolingian Francia and notated from the ninth century, alongside Ambrosian, Mozarabic and Old Roman repertories and the visionary chants of *Hildegard von Bingen*. Transmitted today by monastic choirs such as *Solesmes* and ensembles including *Anonymous 4*, *Sequentia* and *Ensemble Organum*, it is the foundation layer of Western art music.