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Try "le Chanson de Roland", French epic from 11th century...
It's almost exactly what you said:
Deseart (well, not really, more like mountais) - Horn (Roland blew the horn to alarm Charlemagne) - Cavalry (Roland, Olivier, Tupin, and the other 12 peers, knights of Charlemagne) - Heroism (20,000 Frenchman vs. 200,000 Spanish Moors, heroic enough?) - Charge (knights do charge... of course) - Combat (That's out off question...) -Fighting for the country (Mountjoy! For Charlemagne! Yeah, these Frenchmen were patroitic enough) - Sacrifice (Of course, after killing many Moors, all of the 12 peers were slaughtered... basically the book spent half its length describing the detail of how Roland et al. were slautered...)
Otherwise, try Homer's Iliad... you'll enjoy