Bach's cello suites are a compendium of classical music pieces that Johann Sebastian Bach wrote for solo performance with stringed instruments, such as the violin, the viola, and the cello. There are six suites, each composed in a different key and consisting of six movements: a prelude, an allemande, a courante, a sarabande, a galanteries and a gigue. Bach's cello suites were largely forgotten, compared to his sonatas and other works, until the 1925 release of a recorded version by Pau Casals, a cellist who had found a copy of the score in a consignment shop in Spain. Unlike his other compositions, Bach's cello suites were not signed, and the composer did not create annotated performance versions. The suites contain a range of themes and many notable musicians have recorded their own solo performances of one or all of them.
The history of the suites is open to dispute, with no known autographed copies in existence. Traditionally, composers sign their works, and this was standard practice when the suites were composed, sometime in the early 18th century. Some scholars suggest that Bach's cello suites were among his first compositions, while others point to the sophistication of structure as suggesting that Bach composed the works later in his career. A set of Bach's suites, called the "Anna Magdalena" version, was autographed by the composer's wife. Scholars cannot confirm if the Anna Magdalena set was autographed while Bach was alive or if she did so after his death. One theory contends that Anna Magdalena herself composed Bach's cello suites but did not take credit for them.
Scholarship on Bach's cello suites finds consensus on several points, though. The cyclical, ordered nature of each suite, six movements within six structured suites, differs from Bach's other works, especially the violin sonatas. The prelude, courante and gigue movements of Suite Number One in G Major are commonly used in movies, television shows and commercials. In 2002, acclaimed cellist Yo-Yo Ma performed the fourth movement from Suite Number 5 in C Minor at Ground Zero on the first anniversary of the September 11 attacks, as the names of the victims were read aloud. The sarabande of that suite is notable for its somber, slow, and introspective construction.
Bach's cello suites are also regularly performed in their entirety, in solo, duet, quartet, and full orchestral arrangements. The suites have been transcribed for various instruments, including the guitar, the bass and double bass, the piano, the mandolin, and the harp. Variations of each suite have also been written that infuse a wide range of contemporary musical elements into the original works.