Medieval musical was an era of Western music, including liturgical music (also known as sacred) used for the church, and secular music, non-religious music. (jan 1, 500 – jan 1, 1400)
Description:
Hildegard von Bingen and Leonin are two of the biggest composers in the medieval musical era. Hildegard's most significant works were her three volumes of visionary theology: Scivias, Liber Vitae Meritorum; and Liber Divinorum Operum. The details of Léonin’s life are not known. To him is attributed the Magnus liber organi, a collection of two-voiced organum settings, notably of Gradual, Alleluia, and Responsory chants, for the complete liturgical year.
Added to timeline:

Music timeline
Date: