The Mass was commissioned by Jacqueline Kennedy. Leonard Bernstein based the composition on the structure of the Catholic mass, but it contains numerous interpolations, reflections and meditations, rhythmic crowd scenes, bluesy confessions, rock-and-roll doubts and avant-garde instrumental parts based on 20th century symphonic music. Mass sections were composed with the Latin text, the added parts are in English. Despite mixed initial reception, the Bernstein's Mass is perceived as part of the best 20th century classical music due to its undeniable artistic quality. Along with the West Side Story and Chichester psalms it is one of the composer's masterpieces.
The last international stage performance of the Mass in its entirety dates back to 2012 when it was staged with a huge collection of mostly Welsh choral and orchestral ensembles conducted by Kristjan Järvi at the BBC Proms in London. The lead role was sung by the Danish baritone Morten Frank Larsen.