“Reputed to be the hardest work for piano, Balakirev’s 1869 work Islamey saved many a pianist’s weary wrists when it was orchestrated in 1907 by Alfredo Casella,” (Interlude.hk). “Its reputation ensured that both Rubinstein and Liszt had the piano work in their concert repertoire.
… The work as a piano piece is important in Russian musical history because it was the first Russian work to become established in the mainstream repertoire other than as a salon piece. Putting it on the European stage under the fingers of Franz Liszt made the work one of the stars of the new exoticism coming out of Russia. Making it into an orchestral piece extended its reach … Islamey, taking its themes from the Caucasus and Armenia, again brings the remote reaches of Russia back to its main cities. The dedicatee of the piano work, Nikolai Rubinstein, gave the premiere of the work in St. Petersburg in late 1869.”
This landmark composition undergoes many changes in key. But perhaps the most profound occurs at 7:44, when the modulation is also accompanied by a transition in both tempo and time signature — from a frantic 12/16 to to a luxurious Andantino in 6/8.