In 2011, the John J. Burns Library at Boston College acquired a rare exemplar of Cristóbal de Morales’s Missarum liber primus (Lyon: Moderne, 1546) (RISM M 3581-1545/6). This volume, in near perfect condition, is the second edition of the first volume of a two-volume collection of 16 polyphonic masses originally published in 1544 in Rome by Valerio Dorico. The book contains masses composed by Morales (ca. 1500-1553) when he was a member of the Papal chapel.

As a companion to digitized images of the choirbook, the accompanying pages offer students and specialists alike an introduction to this extraordinary collection of sacred Renaissance polyphony. In six chapters, we introduce the composer and the printer, and offer glimpses into the processes that informed the composition of four of the masses. In addition, video and audio recordings invite us into the world of Morales’s superb music.