Shostakovich, Dmitri Dmitriyevich, was a Russian composer and pianist who also was a major figure in 20th-century music. Shostakovich rose to prominence in the Soviet Union under the influence of Soviet chief of staff Mikhail Tukhachevsky, but his subsequent association with the government was complicated and challenging. Despite this, he earned honors and state decorations and worked in the Supreme Soviet of the Russian Soviet Federative Socialist Republic (1947–1962) and the Supreme Soviet of the Soviet Union (from 1962 until his death). Shostakovich, a poly-stylist, created a hybrid voice by incorporating a combination of musical methods into his music. Shostakovich's music is marked by strong parallels, grotesque elements, and ambivalent tonality; the composer was also strongly inspired by Igor Stravinsky's neo-classical form, as well as Gustav Mahler's post-Romanticism (especially in his symphonies). Shostakovich composed 15 symphonies and six concerti for orchestra. 15 string quartets, a piano quintet, two piano trios, and two parts for string octet are among his chamber works. Two solo sonatas, an early collection of preludes, and a later set of 24 preludes and fugues are among his piano compositions.