The Cello Sonata (Sonate pour violoncelle et piano), L. 135, is a sonata for cello and piano by Claude Debussy. It was part of his project Six sonatas for various instruments to compose six sonatas for different instruments. It consists of three movements: Prologue, Sérénade and Finale. It was composed and published in 1915. After performances in London and Geneva in 1916, the sonata's official premiere in Paris was played in 1917 by Joseph Salmon and Debussy. It was the first chamber music work in his late style, and became one of the key works in the repertoire from the 20th century. History and background Debussy composed the cello sonata as the first in a project, Six sonatas for various instruments, to compose six sonatas for different instruments. It was prompted by a performance of the Septet by Saint-Saëns, inspiring Debussy to write chamber music again which he had neglected since his string quartet of 1893. Diagnosed with colorectal cancer in 1910, he had not composed at all. Debussy's publisher Durand encouraged the project, planned as homage to 18th-century composers Couperin and Rameau. Throughout his career, he preferred the French keyboard music of the 18th century over German romanticism. To remain in the French tradition was also a political statement during the World War. He described himself as a French musician on the title pages of project pieces. Debussy planned three movements, as in French traditional sonatas. He had written many works in three movements such as Pour le piano, En blanc et noir, and Iberia. Debussy composed the Cello Sonata as the first of the set within a few weeks in July at the Normandy seaside town of Pourville. He wrote to his publisher Durand on 5 August that he would send the manuscript of what he described as a sonata in "almost classical form in the best sense of the word". It was printed in December 1915. Despite other information, the sonata was premiered in London's Aeolian Hall by cellist C. Warwick Evans and Ethel Hobday on 4 March 1916. It was played at the Casino Saint-Pierre in Geneva, performed by cellist Léonce Allard and Marie Panthès. It took until 24 March 1917 for the French premiere which was given in Paris by cellist Joseph Salmon and Debussy. The cellist Louis Rosoor claimed in program notes that Debussy related the music to the character Pierrot of the commedia