The three works Isaac composed for the Maximilian court that quote the chant Virgo prudentissima represent a thematic unit adhering to the ideological and liturgical goals of the court, acting as a grand plea to the Virgin Mary. The antiphon Virgo prudentissima is liturgically appropriate because it glorifies Mary and her Assumption and Coronation, which is symbolically aligned with Maximilian’s coronation. In his six-voice Virgo prudentissima motet, Isaac emphasizes key phrases in the cantus firmus that directly address Mary by shifting into a homorhythmic style. Like the unusually grand motet, Missa Virgo prudentissima is unusual in Isaac’s work. It is Isaac’s only six-voice cyclic Mass based on a chant, but its earliest source is in a collection of six-voice polyphony and alternatim Masses, suggesting an alternatim reconstruction of the Mass is possible. The shared use of the Virgo prudentissima and other stylistic similarities between the coronation motet and the mass would call to mind Maximilian’s coronation during the annual performance of the Mass on the Feast of the Assumption. This strong connection between the Virgo prudentissima antiphon and the Maximilian court in Isaac’s work suggests that music found in manuscript CCII, thought to be composed exclusively for the Cathedral of Constance, could have been used at Maximilian’s court as well. The Introit Gaudeamus omnes V. Exaltata es contains a conspicuous use of Virgo prudentissima as a secondary cantus firmus, connecting this Introit to the Maximilian court compositions. Taken as a unit, these Virgo prudentissima compositions work to appeal to the Virgin Mary directly as the protector of Maximilian, aligning with his cultivated image as the Wise King.

Works: Isaac: Virgo prudentissima (six-voice motet) (48-57), Missa Virgo prudentissima (57-67), Gaudeamus omnes V. Exaltata es (67-73)

Sources: Antiphon: Virgo prudentissima (48-73)

Index Classifications: 1500s

Contributed by: Matthew Van Vleet