This thread about Schulhoff reminded me of another composer who was killed
by the Nazis because he was a Communist (I do not think that he was of
Jewish ascent), Vojislav Vuckovic (Serbia, 1910-1942).

Actually, I am not particularly interested in his "late" works, which
apparently followed the lines of socialist realism, but his earlier works
(such as Symphony No. 1) are said to be very daring and innovative.  Would
anybody have an idea of where it could be heard? Apparently it cannot be
found in record stores, even in Belgrade.  Music of the 1920s and 1930s in
Central Europe is a real treasure box.  Now we can finally enjoy the music
for itself, even if it was sometimes more vivid and full of imagination
than thoroughly controlled and refined.  For instance, do you know Slavko
Osterc (Slovenia, 1895-1941)? This is a real master, tending on the
neo-baroque, with affinities with Hindemith, Berg, Stravinsky, but very
much his own man, music of much substance and sometimes exhilarating power
too.  The Slovenian radio recorded a CD of orchestral works, including "4
symphonic pieces" (sometimes known as Symphony No. 2).  I eagerly await
the moment when their records can be ordered on-line.

In a very different style (many styles, actually), Josip Stolcer Slavenski
(Croatia, lived many years in Belgrade too, 1896-1955) is a remarkably
original composer, a "primitivist" who followed his pure intuition but
could achieve moments of striking complexity and originality, even
spirituality (with nothing of upcoming New Age trends...).  His Simfonija
Orijenta (Religiofonia) evokes all monotheistic religions, including
communism (!!!), and this is a most surprising fresco.

Other names would be Lithuania's Juozas Gruodis and Jeronimas Kacinskas,...

I have been looking unsuccessfully for reputedly magnificent works of this
period and region, notably: Symphony No. 2 "Swiety Boze" by Jan Adam
Maklakiewicz (Poland, 1899-1954) and Dimitar Nenov (Bulgaria, 1902-1953)'s
two symphonies.  If you know anything about them, please let me know!

Best wishes,

Thanh-Tam Le