In 1911 a group of folklorists set out from St Petersburg to comb the Russian shtetls for Jewish songs and chants. Inspired by Nikolai Rimsky-Korsakov and led by the playwright Shloyme Ansky – author of The Dybbuk – they wanted to record this oral tradition before it evaporated for good. The resulting collection of cylinders was so impressive that the incoming Bolsheviks decreed the work should continue, and they put their own man in charge. Moisei Beregovsky was a loyal Stalinist but an excellent folklorist, and until his deportation to Siberia in 1949 he recorded and meticulously transcribed several thousand more songs and texts. When he was released in 1955 the cylinders had disappeared, and it was generally assumed that his unique archive had been destroyed.

Forty-four years later Israel Adler, professor of musicology at the Hebrew University of Jerusalem, announced a discovery. The director of the National Library in Kiev had come to see him about photocopying manuscripts. ‘And seeing our cylinder collection, he mentioned that he too had some cylinders, which the American Library of Congress had looked at without much interest. Could this be the Beregovsky collection? I jumped on the first available plane to Kiev, and discovered that it was.’

Even leaving aside the awkward matter of past pogroms, the course of the ensuing affair was bumpy, with Kiev raising endless obstacles to the digitisation of the recordings Jerusalem wanted. While Adler’s aim was to make the archive available to scholars all over the world, Kiev’s aim was to make a profit. But as a Berlin-born Ost-Jude, Adler took this sort of thing for granted. ‘Whenever things seem discouraging, I listen again to these marvellous recordings,’ he told me. ‘Then I am re-inspired.’ To illustrate the point, he played some examples: a Bartókian country song with driving rhythms; a dance sounding as if it was straight out of Fiddler on the Roof; and an austerely beautiful liturgical chant. When the latter was broadcast on Haifa Radio, Adler said, a middle-aged Israeli rang in to say that he recognised the voice of the cantor: his own grandfather.