How did one composer document, and survive, the 20th century’s most brutal political experiment?

Beginning in St Petersburg in 1906 and ending in Moscow in 1975, the life of Dmitri Shostakovich coincides with the greatest political experiment in modern history – the entity that was the Soviet Union. And perhaps no other composer better represents the vicissitudes and ambiguities of those times.

A man whose early works exude enthusiasm and the desire to give the world a jolly good shake-up, in some respects Shostakovich followed in the revolutionary footsteps of Lenin and Trotsky. By the time it all went wrong and the leaden weight of Stalinism had been brought to bear on the state, and Soviet art in general, Shostakovich’s music had begun to take on the qualities that were to become indelibly associated with the times: public glorification of the regime, private despair and, most obvious to us today, an ambiguity and irony expressed through music – a language behind which some might think only the brave or foolhardy would try to hide.

So which was he? Musical apologist or counter-revolutionary? A cleanliness obsessive who sent himself cards to check that the postal service was working correctly, Shostakovich was...