During the 1432 session of the General Court of the Principality of Catalonia, held in Barcelona, it was decided that a chapel to Saint George should be constructed at the Palau de la Diputació del General (Palace of the Principality of Catalonia, now called Palau de Generalitat de Catalunya, or Palace of Government of Catalonia). Saint George is the patron saint of the Diputació del General. At the end of the 16th century, the new chapel—today known as Saint George’s Hall—was built in order to accommodate the mass of people who would gather on the days of great celebrations, such as April 23, Saint George’s Day. This manuscript contains the collection of polyphonic religious compositions intended to be sung in celebrations at the chapel. The composer is Joan Pau Pujol (1573−1626), who presented the works to the ecclesiastic, civil, and military deputies of the Diputació del General in 1623−26. According to musicologist Higini Anglès (1888−1969), the manuscript is in Pujol’s hand. A composer and organist, Pujol was a key figure in Catalan music of the 17th century. He is regarded as the link between the later Renaissance and the early Baroque in Catalonia. He was chapel master at the cathedrals of Tarragona (1593−95), El Pilar de Zaragoza (1595−1612), and Barcelona (1612−26) and wrote many religious and secular works, using polychorality with impeccable technique featuring the combination of solo voices and choirs with a rich counterpoint. Pujol was also known internationally, and many of his works were found in outstanding songbooks in different countries. In spite of this, Pujol’s compositions were not published, and only at the beginning of the 20th century were his works recovered by the musicologist Felip Pedrell (1841−1922). This manuscript is distinguished by the accuracy of its musical notations. The first four initials are illuminated in the incipit of each voice, the first one having the figure of Saint George. The binding is made of brown leather with gilts, with the Cross of Saint George (the coat of arms of the Diputació del General of Catalonia) engraved on the front cover. The document is from the magnificient collection gathered by the composer and bibliophile Joan Carreras i Dagas (1828−1900). Subsequently, Pedrell designated it number 389 in the first volume of the collection catalogue, published in 1908.