Welcome to Gaffurius Codices Online (GCO), a website dedicated to the four manuscripts of polyphonic music prepared by Franchinus Gaffurius for the Duomo of Milan in the decades around 1500. Gaffurius (1451–1522), a music theorist and composer, was chapel master at the Milanese cathedral from 1484 to 1522.

The four large-size manuscripts, also known as Libroni (‘big books’), are among the most important extant sources of sacred polyphony for the period. Not only they attest to the repertory performed in the Duomo, but they are the sole, albeit indirect, testimonies of the rich musical culture at the Sforza court.

The manuscripts (the last of which, severely damaged in a fire in 1906, is only fragmentarily preserved) contain music by such composers as Josquin des Prez, Loyset Compère, Gaspar van Weerbeke, Heinrich Isaac, and Jacob Obrecht, besides Gaffurius himself. The corpus comprises more than two hundred motets (and several motet cycles, including the famous motetti missales), 40+ mass settings, 30+ Magnificats, seven hymns, two Te Deums, a set of Lamentations, one Italian lauda, and four textless compositions.

If you want to browse the manuscripts, start here.

If you want to access detailed metadata, explore the Inventories and Catalogues.

If you are interested into modern editions of selected compositions, go to Editions.

For further resources and bibliography, go to Resources.

If you need help, consult the User guide.


This website (first published in November 2019) is maintained by the SNF Project Polifonia Sforzesca: The Motet Cycles in the Milanese Libroni between Liturgy, Devotion, and Ducal Patronage (Schola Cantorum Basiliensis FHNW, 2018–2020).

Interlinked with other online reference works (notably the Motet Cycles Database), it is provided as an open-access research tool of interest not only to musicologists and musicians, but also to students and scholars in various disciplines (from codicology and palaeography to liturgy and Sforza studies).