Like changing the course of a river, redrawing the horizon or coming up with a new law of nature: the groundbreaking work of the Notre-Dame School around the year 1200 changed music history for good. The wonder that the Parisian pioneers created is called the ‘organum’: a pioneering technique in which several voices move simultaneously along their own melodic line. This was a radical change of tack in a period when most music was monophonic! What shocked the community at the time is now considered to be gorgeous mediaeval art, offering a glimpse of genius behind every score. Huelgas Ensemble sings famous works by Léonin and Pérotin – both of whom were choirmasters at Notre-Dame – along with conducti and motets by anonymous composers, including Laudes regiae, a royal tribute for Eastertide.