The Cambridge Companion to Mendelssohn by Peter Mercer-Taylor

'Mendelssohn' is a name directly connected to 'J.S.Bach'.

When 'J.S.Bach' was already a forgotten composer for long decades, Mendelssohn visited many libraries and public collections, then finds ultra-dusty and deteriorated sheet music of an unknown countryman he barely knew, of course he had heard of the Bach family, and knew classical works by Karl Phillip, or Mozart's ex-teacher 'Johann Christian Bach' that influenced much the music of Mozart Style

But, when 'Mendelssohn' played the old German composer 'J.S.Bach', he perceived something very sophisticated in his counterpoint such a method of composition that wasn't used for a long time, when he started to include some pieces of his compatriot in his own concerts and auditions, the public adored, it was a novelty.

Later he found in a public library in Germany, the 'Mass in B minor - St. Matthew Passion', when in 1829 in Berlin, he just played some fragments of it, the public didn't believe that it would have been done by a German, from that day on, Bach never ceased to be played, and almost all his work could have been lost by the neglect and ill-treatment of human ignorance for the old things and the past.

Later he took care to find all Bach's manuscripts, concerts, masses, and oratorios to be reprinted and preserved as world heritage of humanity.

Thank you Mendelssohn for this great feat, know that you are actually the composer of two great works for mankind, one of them the 'J.S.Bach', which could have stopped in the trash by simple deterioration and lack of publications.