Historical Dictionary of Russian Music by Daniel Jaffé EPUB [EN]

Balakirev: His most famous work, Islamey, is based on Spanish and Arabic themes, also he became famous for its amazing orchestration on the Polish Chopin—what a shame—he really failed miserably, his Russian music did not even happen on the planet. Even so, I’m a huge fan of Balakirev, I would have loved to have him as a teacher—though I certainly wouldn’t have shared his fate.
(For example, “Take Five,” often credited to Dave Brubeck, was actually composed by Paul Desmond. Likewise, Duke Ellington’s signature piece “Take the ‘A’ Train” was written and arranged by Billy Strayhorn.
So whenever someone offers you a tune that starts with “Take,” you might just want to politely decline, don't accept it.)

César Cui: Virtually forgotten today; few know his music.

Mussorgsky: Achieved lasting fame only because Ravel orchestrated Pictures at an Exhibition. Without that French intervention, he might be unknown.

Borodin: Like Stalin, born in Georgia (then part of the Russian Empire). His best-known music is from the opera Prince Igor, especially the “Polovtsian Dances.”

Rimsky-Korsakov: Arguably the purest Russian of the five, unique — yet he secretly organized avant-garde concerts on Tuesday nights, featuring modern music from across Europe.

Finally, a few other great Russians:

Tchaikovsky: One of the world’s most famous composers, whose tragic personal life—strained relationship with the nephew of a prominent jurist—ultimately was induced to commit suicide.

Stravinsky: Rejected at home, he found fame in France; thankfully, he survived.

Rachmaninoff: In his own time, he wasn’t respected by the Russians. Scorned in Russia, he only achieved renown after emigrating to the United States.

But above them all stands Rimsky-Korsakov and Rachmaninoff—truly the greatest of Russia. Fascinating.