Messe solennelle is a setting of the Catholic missa solemnis by the French composer Hector Berlioz. It was written in 1824, when the composer was twenty, and first performed at the Saint-Roch, Paris, on 10 July 1825, and again at the Saint-Eustache in 1827. After this, Berlioz claimed to have destroyed the entire score, except for the Resurrexit, but in 1991 a Belgian schoolteacher, Frans Moors, came across a copy of the work in an organ gallery in Antwerp, and it has since been revived.
The Long Line