Hannibal was famous for crossing the Alps (218BC) with his elephants, and for using the animals in his battles against Rome during the Punic Wars.
But long before elephants it was the use of camels that proved effective in War.
The "Battle of Thymbra" took place in 546BC.
Cyrus the Great (Cyrus II) sought to expand his rule, and the rule of the "Persians," in the central and southern regions of Asia (modern-day Iran).
He was forcefully opposed by the "Lydians," a small empire that had itself arisen from the fallen Hittite kingdoms nearly five hundred years before. There was much wealth to be found in conquering these people, and the warfare between Cyrus and the Lydian King Croesses was vividly detailed in the histories of the day.
Cyrus was pressing against Croesses, seeking the fabulously wealthy city of "Sardis," when he devised a plan to use camels as weapons in his attack. These were pack-animals, but the camels were instead placed in the front of the marching army, and as the Persians approached the Lydians it was the Lydian horses that withdrew in terror. The horses feared the smell of the camels and they reared back, throwing off their riders, and it was not difficult for the Persians to rush forward, cutting down man after man... until they soon found themselves ankle-deep in Lydian blood. The battle quickly became a massacre, and it secured Cyrus' position over Lydia.
Cyrus would continue his quest for "Empire" and soon captured territories in Greece, Babylonia, Syria, Egypt, and Palestine -- with his camels in battle beside him.
Cyrus' grandson, "Darius I," would later become famous in the Persian conflicts against the Greeks and the "Battle of Marathon" in 490BC.