Chorus, the name for a community of singers that evolved in Europe from the Middle Ages onwards, derived from the choros of Ancient Greek theatre. The first polyphony soon arose from the initially purely monophonic Latin church music, sung since Late Antiquity and collected and standardized under Pope Gregory I as Gregorian chant. The Renaissance then brought forth complex types of polyphonic a cappella works - these reached new heights during the course of the 16th century in multiple choirs, bringing new experiences in sound through the juxtaposition - whenever space allowed - of several choirs inside churches. The choir became increasingly functional - above all in operas, cantatas and oratorios. By the Late Baroque period, the development stage had been reached that still characterizes today's concept of the choir: a fixed choral ensemble, clearly differentiated from an instrumental one; works of primarily spiritual content; texts in Latin but, increasingly, in national languages as well; and everythin ggradually becoming more representational in character. The Chor des Bayerischen Rundfunks can be heard here performing highlights of sacred choral music dating from the Baroque period to modern times. Even today, three hundred years later, the large oratorio choirs by Bach and Handel are as vivid, realistic and captivating as ever. Haydn succeeded in preserving this for the sacred music of the Wiener Klassik era, which reached its peak in Beethoven's Missa solemnis. The heartfelt masses composed by Schubert are typical of early German Romanticism, Gounod's St. Cecilia Mass is the French equivalent here, and Dvorak's Stabat Mater represents Bohemian Romanticism of the mid to late 19th century. Verdi's famous Messa da Requiem testifies to the close relationship between Italian opera and Italian church music. The Mass written just before the end of World War II by the Hungarian composer akodaly is still Late Romantic in its musical language, while in his Berlin Mass, written shortly before the start of the 20th century, the Estonian composer Arvo Part maintains the Tintinnabuli style that informs and inspires his work. This representative cross-section of well-known and some less well-known choral numbers spans a period of almost three hundred years, impressively demonstrating not only what gives choral music its special character and aura, but also what has changed over the centuries and what has remained largely similar. Furthermore, it testifies to the unique choral culture of the Chor des Bayerischen Rundfunks and to the "crystal clear sound" and "immense plasticity" of its performances, which are regularly praised in the highest terms, along with supreme artistic quality of its interpretations.