Most underrated composer of 20th Century?

It's a tie between Martinu and Janacek.

Great minds think alike Rpfef, Janacek was my second choice, tie-breaker was he's much better known.

I guessing probably some well known composers of music in eastern culture totally unknown in the west, much less underrated?

Duke Ellington is far from unknown, but still hugely underrated as a top echelon 20th century music composer overall IMHO.

In more traditional classical music world, how about Villa Lobos? He is high on my list of classical composers to explore deeper based on what I have heard to date.

Western classical music has always had a heavy European bias, for clear historical reasons. Are the most underrated composers of the 20th century likely to still be mined in those waters?

Villa Lobos is certainly right up there, his string quartets were a big surprise to me.

Problem I have with Ellington is you never know what was written by Strayhorn.
Sorta like Beethoven publishing Schubert work as his own.

Western classical music has always had a heavy European bias, for clear historical reasons. Are the most underrated composers of the 20th century likely to still be mined in those waters?

Mapman is asking the question that - as a person whose interest in classical music is equal parts aesthetic and anthropological - probably interests me more than any other.

I would speculate that increased appreciation of alternative musical languages is probably an inevitable result of the shrinking world around us. I'd also expect that compositions employing microtonal scales (whether from Asia or from Western composers who borrowed the approach) will gain more attention from critics and scholars. The evolution of the legacy of Harry Partch, et al will be interesting to watch.

Similarly, it will be interesting to see how the big names of the second half of the century hold up. Will Phillip Glass end up as the most underrated composer of the century or the most overrated? Which also raises the question of opera and its place in this question. Where does Alban Berg belong?

I'm not really proposing any candidates here, just following up on Mapman's interesting observation.