Which composer contributed new musical settings to the mass after its decline?

The composer who contributed new musical settings to the mass after its decline is Fauré. Gabriel Fauré was pivotal in reimagining the liturgical music of his time, particularly through his renowned work "Requiem," which, while not a traditional mass setting, reflects significant stylistic innovations in sacred music. His approach emphasized a more lyrical and expressive quality, which rejuvenated the mass form during a period when it was seen as less relevant due to the rise of operatic and symphonic music.

Fauré's compositions influenced subsequent generations of composers and contributed to an evolution in the way sacred music was perceived and performed, laying groundwork for later musical explorations in church settings. This focus on beauty and emotional depth distinguishes Fauré's contributions and highlights the significance of his role in revitalizing mass settings during this era.