I’m no more than an admirer, but I would recognize this score from its opening measures without the title. And I couldn’t go through life captivated by it but never having attempted it, so I did manage to work through the first third or so of Segovia’s arrangement of it for guitar. This is J. S. Bach’s Chaconne from Partita No. 2 for solo Violin (D minor), here performed by Jascha Heifetz, Paris, 1970.
Bach composed this work (1720, together with the other sonatas and partitas for solo violin) just after the death of his beloved wife Anna. One story about the composition (believed by many musicians but few Bach scholars) is that Bach’s elaborate use of the double stop (playing two notes at once) strewn throughout was Bach’s way of retrieving Anna from the grave to rejoin him and unite her voice with his. Well, true or not, the partitas are sublime, and the Chaconne is their summit.