The Violin Sonata, Op. 134 was written in honor of David Oistrakh’s 60th birthday and premiered in Moscow on May 2, 1969, with Oistrakh and Svyatoslav Richter performing. Oistrakh was a close friend of Shostakovich and served as the composer’s main inspiration for both of his violin concertos. The Viola Sonata, Op. 147 was Shostakovich’s last work. It was dedicated to the violist Fyodor Druzhinin, a professor of the Moscow Tchaikovsky Conservatory and a member of the Beethoven String Quartet, a renowned Moscow ensemble that played at the premieres of most of Shostakovich’s string quartets. Fyodor Druzhinin and Mikhail Muntyan premiered the Viola Sonata in Leningrad on October 1, 1975.