The Modena Codex (Modena, Biblioteca Estense, I-MOe5.24, also known as ModA) is an Italian manuscript of medieval music dating from the early fifteenth century. It contains an extraordinary variety of musical works, numbering 104 in total. The Modena Codex, together with the equally-famous Codex Chantilly and the Reina Codex is considered one of the most important sources of Ars Subtilior polyphony, which flourished in the relatively short period between c.1380 and c. 1420 and which is often characterised by intricate rhythmic complexity and bold harmonic experimentation.
The Modena Codex contains many simpler works as well, such as the delightful rondeaux by Matteo da Perugia. Besides courtly love songs, the manuscript contains motets, mass sections and canons. Many of the French songs were written by Italian composers.
The precise origin of ModA has been subject to discussion, with Bologna as the most probable choice. It is a rather modest manuscript of only 51 parchment folios split into five gatherings. It is certain that the original order of the gatherings was later changed. The middle three gatherings are often beautifully illuminated and contain most of the Ars Subtilior repertoire and a number of Trecento works; the outer gatherings are decorated in a rather plain style and contain almost exclusively works by Matteo de Perugia, accounting for more than 90% of his known output.
Apart from Matteo de Perugia, The Modena Codex contains various compositions by Antonello and Philipoctus da Caserta, Antonio Zacara da Teramo, Jacopin de Senleches, Guillaume de Machaut, Francesco Landini, Johannes Ciconia, Corradus de Pistoria, Egardus (a Flemish composer), Egidius, Bartolino da Padova, Bartolomeo da Bologna, Johannes de Janua, Matheus de Sancto Johanne, Johannes Galiot and Andreas Servorum.