The title-page of Elgar’s autograph for his “Enigma Variations” reads: ‘Dedicated to my friends pictured within. Variations for orchestra composed by Edward Elgar op. 36’ (no mention of any ‘enigma’).
There are precedents for musical portraits in Mozart, Schumann and Tchaikovsky. Portraiture allowed Elgar the freedom to write variations that depart from the structure and harmonic layout of his theme, unlike the stricter variations of, for instance, by Bach or Brahms.
At the head of each variation, the friends are identified by initials, or are otherwise lightly disguised. Elgar told A.J. Jaeger (Var. IX, ‘Nimrod’) that this private matter was of no interest to audiences.
The friends were mostly from Mrs Elgar’s social circle (a cut above Elgar’s, whose father was ‘in trade’). Only three were professional musicians: ‘Nimrod’, who worked for Elgar’s publisher Novello; Var. XI, ‘G.R.S.’, George Sinclair, organist of Hereford Cathedral (though the variation concerns the antics of his dog, Dan); and Elgar himself, in the finale, lightly disguised as ‘E.D.U.’ (‘Edu’ was his wife’s affectionate reduction of ‘Edward’).
Here is an extract of this amazing music, Elgar’s Enigma Variations: