Unconventional, but engaging.
Very dark and has that nice off-kilter (3/4) feel for devious marches. :)
Is that an anvil I hear back there? It really needs more reverb. Don't be afraid of adding some really deep strings under there too as a drone, that'd make it stronger... even a timpani roll could do that too. Another nice idea would be a loud bass drum to hit on the 2nd and 3rd beat to counter the timpani. Don't be afraid to bring your percussion louder (esp. timpani). At 0:52/0:54, I was expecting the song to widen up with some serious instruments.
During some periods, it might be nice to hear a trombone counter-melody. You used them (or something that sounded like them) extensively, but a quieter variation could be used to great effect with quick walking-bass-esque phrases under some string parts. (eight notes, climbing the minor on the first 4, then turning into the 5th, so A-B-C-D-F-E; then changing for the next chord and so on in the background a little). It's good to see someone else who works with the sixth chord a lot. :)
1:24 was especially lacking that deep element I was talking about before... I could feel a need for a descending bassline there with measure whole notes to accent the changes. Lastly, you should consider looking into various types of endings and find one that works. The old 'fade out' doesn't cut it for marches unless you're going for a feel.
Really a great piece, Perhaps I'll check out some more of your work in the future. Keep it up!
-Samulis