When did the mass begin to decline significantly?

The mass began to decline significantly during the 20th century as a result of multiple social, cultural, and musical developments. The first half of the century saw the rise of popular music genres, such as jazz, blues, and eventually rock and roll, which began to dominate the musical landscape. These genres changed how audiences engaged with music, moving away from traditional liturgical settings to more secular entertainment forms.

Additionally, the 20th century experienced substantial changes in society, including shifts in religious practices and a growing emphasis on individualism, which contributed to the diminishing role of the mass in community life. The introduction of new technologies, such as radio and television, also transformed how music was consumed, further drawing attention away from traditional forms like the mass.

In contrast, the mass was at its height and most influential in earlier centuries, particularly during the Renaissance and Baroque periods, when it was a central part of religious and cultural life in Europe. By the time the 19th century arrived, while there were still significant choral traditions and adaptations of the mass, the overall cultural and social changes were paving the way for its decline, solidifying more in the following century.