As his health deteriorated, Schnittke's music started to abandon much of the extroversion of his polystylism and retreated into a more withdrawn, bleak style.

His mother, Maria Iosifovna Schnittke (née Vogel, 1910–1972), was a Volga German born in Russia.

Schnittke's paternal grandmother, Tea Abramovna Katz (1889–1970), was a philologist, translator, and editor of German-language literature.

"[11] "I felt every moment there," the composer wrote, "to be a link of the historical chain: all was multi-dimensional; the past represented a world of ever-present ghosts, and I was not a barbarian without any connections, but the conscious bearer of the task in my life.

It was Mozart and Schubert, not Tchaikovsky and Rachmaninoff, whom he kept in mind as a reference point in terms of taste, manner and style.

He experimented with techniques in his film work, as shown by much of the sonata appearing first in his score for the 1968 animation short The Glass Harmonica.

Other works were more stylistically unified, such as his Piano Quintet (1972–1976, later orchestrated and retitled as In Memoriam…), written in memory of his mother, who had died in 1972.

This period was also marked by a turn in Schnittke and his music to Christian themes, exemplified in his deeply spiritual unaccompanied choral works, the Concerto for Mixed Chorus (1984–1985) and the Penitential Psalms (1988), and alluded to in various others works, including the Fourth Symphony and the Faust Cantata.

[21] As his health deteriorated from the late 1980s, Schnittke started to abandon much of the extroversion of his earlier polystylism and retreated into a more withdrawn, bleak style, quite accessible to the lay listener.

[23] He did complete some short works in 1997 and also a Ninth Symphony; its score was almost unreadable because he had written it with great difficulty with his left hand due to his strokes.

[24] The Ninth Symphony was first performed on 19 June 1998 in Moscow in a version deciphered – but also 'arranged' – by Gennady Rozhdestvensky, who conducted the premiere.