In 1873 at the age of thirty-nine, Viktor Alexandrovich Hartmann, Russian architect and painter, died from an aneurysm. He was at the forefront of the Russian Revival, friend of and inspiration to many contemporaries in the field of architecture, art and music. Shortly after his death, Vladimir Vasilievich Stasov, helped to arrange an exhibition of Hartmann’s work.
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Mussorgsky poured out his feeling about his friend’s death in a letter to Stassov. who shared the Russian nationalist tendencies of Hartmann and Mussorgsky and had brought the two men together in the first place.
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Mussorgsky’s piano suite was not published until after his death, is dedicated to Stassov. Stassov, with whom Mussorgsky had discussed the suite as he composed it, explained in the first edition of the Pictures at an Exhibition: “The composer here portrays himself walking now right, now left, now as an idle person, now urged to go near a picture; at times his joyous appearance is dampened, he thinks in sadness of his dead friend. …”
http://korschmin.com/pictures-at-an-exhibition/

Sir Georg Solti – Chicago Symphony Orchestra 1980