The horn's loud, lugubrious tones "suited the tumult of war," wrote Diodorus Siculus around 50 B.C. Later Roman troops used the karnyx themselves.

Perseus of Macedon prepared for a Roman attack with war elephants in 168 B.C. by having artisans build wooden models of elephants on wheels.

in 202 B.C., blasts of Roman war trumpets panicked Carthaginian general Hannibal's war elephants in the Battle of Zama, ending the Second Punic War.

In 280 B.C., the Romans first encountered war elephants, brought to Italy by Greek King Pyrrhus.