The Messe des pauvres (Mass for the Poor) is a partial musical setting of the mass for mixed choir and organ, written from 1893 through 1895 by Erik Satie. It was intended for liturgical use in the Metropolitan Church of Art of Jesus the Conductor. The mass is Satie's only liturgical work and the culmination of his "Rosicrucian" or "mystic" period. It was published posthumously in 1929.

A performance lasts around 18 minutes.

In the early 1890s, Satie's fascination with medieval Catholicism, Gothic art and Gregorian chant led him to explore religious influences in his life and music. At first he was drawn to Joséphin Péladan's Rose + Croix movement, for which he acted as official composer from 1891 to 1892, and after breaking with Péladan he associated with the occultist writer Jules Bois, publisher of the religious esoteric journal Le coeur. At the same time he was immersed in a bohemian lifestyle as a pianist at Montmartre cabarets, where his already eccentric behavior took on a growing penchant for buffoonery and exhibitionism.

This paradox came to a head in October 1893 when Satie founded his own mock religious sect, the Église Métropolitaine de l'Art de Jésus Conducteur (Metropolitan Church of Art of Jesus the Conductor), with himself as High priest, choirmaster, and sole member. It was a spoof of the flamboyant Péladan, whose Rose + Croix creed ("the transformation of society through art") and habit of "excommunicating" his critics in bombastic letters to newspapers Satie gleefully adopted. He carried the charade into his daily existence, dressing in monkish robes and referring to his tiny room at 6 Rue Cortot as his abbatiale (abbey). "[Satie] liked to affect the unctuous manners of a priest," his friend Francis Jourdain recalled. "They suited him so well, he played his part so accurately - being careful not to overdo things - that the question arose as to whether a slightly false air was not innate in him."

Against this background, Satie's motives for writing the Messe des pauvres - the sole composition linked to his church - are obscure. Originally entitled Grande Messe de l'Eglise Métropolitaine d'Art, it was his most ambitious work to date, although there was no evident prospect of having it performed. Satie authorities Ornella Volta and Robert Orledge believe he conceived the mass to occupy his mind following his recent breakup with the painter Suzanne Valadon, which had left him emotionally devastated. At the midpoint of their turbulent six-month affair in March 1893, Satie had composed his Danses gothiques as a "Novena for the great calm and profound tranquility of my Soul"; similarly, the first mass movement he completed (in late 1893) was the Prière pour le salut de mon âme ("Prayer for the salvation of my soul"). It is unknown how the mass assumed its final title Messe des pauvres. The texts Satie chose make no reference to the poor at large, giving further weight to speculations that, impoverished as he was, he essentially wrote the mass for his own solace.

In 1895, a substantial cash gift from a friend enabled Satie to publish a series of tracts in which, under the guise of his church, he criticised those of whom he disapproved. Portions of the Messe des pauvres appeared in two of them: an extract from the Commune qui mundi nefas in a pamphlet of the same name (January 1895), and the complete Dixit Domine - calligraphed in faux Gregorian notation by Satie - in the brochure Intende votis supplicum (March 1895). The only contemporary account of the mass is an article by the composer's brother, Conrad Satie, published in the June 1895 issue of Le coeur. He described it as a work in progress, humbly scored for organ and a choir of children's and men's voices. "This mass is music for the divine sacrifice, and there will be no part for the orchestras which, I'm sorry to say, find their way into most masses," he wrote. He also made an intriguing statement about its structure: "Between the Kyrie and the Gloria a prayer is inserted called Prière des orgues." The Gloria movement was not found in Satie's posthumous papers and is considered lost.

Soon after his brother's article appeared, the unpredictable Satie lost interest in his church, the mass, and in composition altogether. That same month he exchanged his robes and religious affectations for the seven identical sets of corduroy suits that would come to define his "Velvet Gentleman" phase, and for the better part of two years he wrote nothing. In his next important work, the Pièces froides for piano (1897), Satie revisited the pre-Rose + Croix style of his Gnossiennes and turned his back on the mystical-religious influences he would later dismiss as "musique à genoux" ("music on its knees"). The mass was not performed during his lifetime.

After Satie's death in 1925, his friend and music executor Darius Milhaud brought the forgotten manuscript of the Messe des pauvres to light. Three of the movements (the Prière des orgues, Commune qui mundi nefas, and Prière pour le salut de mon âme) were premiered by organist Paul de Maleingreau at the Concerts Pro Arte in Brussels, Belgium, on May 3, 1926. An early complete performance was led by Olivier Messiaen at the Église de la Sainte-Trinité, Paris on March 14, 1939. The work was first recorded in 1951.