Trunks and Tusks: The Terror of Rome
When readers hear about ancient war elephants they see the Oliphaunts of the Lord of Rings charging through ranks of men. They see tusks impaling men, huge feet smashing through lines, and men being hurled around like rag dolls by the elephants trunk. It gives the idea of a game changing weapon that obliterated all comers. While an elephant is completely capable of eradicating a single man, it's use in the battlefield was not so simple.
East and West
Elephants were used in both the East and the West. Their purpose differed slightly in both areas due to the number of elephants available, their size, and the forces they faced. This means that elephantry, a division of war elephants, must be understood in two separate realms.
In the east, where elephantry developed, elephants were larger, stronger, and had larger availability. This allowed towers to be mounted on top of elephants, giving them the ability to carry more soldiers than the west, as well as carrying heavy war-machines, like giant crossbows. This meant that elephantry was able to act as an independent division with little support from other forces.
In the west elephants were smaller. They were also over-harvested to the point that they went extinct. Western elephants could carry howdahs, small firing platforms for two to three infantrymen, but were rarely suited for large towers or war-machines. Therefore in the west elephantry was used primarily to shock and disrupt the enemy while the rest of the army moved in to combat range.
Further reading on the Punic Wars
Battles involving Elephantry in the West
In the western world Elephants were primarily used in the wars between Carthage and Rome. The Punic Wars set Rome on the path to dominate the Mediterranean, while Carthage was obliterated. Carthaginian elephantry was used extensively in the first Punic War and to a lesser degree in the Second Punic War. Throughout both wars the elephantry failed to provide any serious battlefield damage, but they terrified the Romans nonetheless.
In the First Punic War the Carthaginian armies used elephantry extensively in all of the major land battles. Rome and Carthage were fighting over Sicily, a mountainous island, which meant that much of the war was fought in small skirmishes rather than battles of line infantry. At the Siege of Agrigentum,in Sicily, and the Battle of Adys, in Africa, the Carthaginians fought in mountainous ground and their elephants were broken or captured with ease because they could not deploy in massed attacks.
At the Battle of Tunis Carthaginian forces successfully deployed their elephantry, but it was the Carthaginian cavalry that actually broke the Roman lines. This is where the Roman fear of elephantry came from. Few Roman troops survived the Battle of Tunis, and when the returned to Sicily they spread fear of the elephants throughout the other consular armies. The elephantry became an easy scapegoat for the Roman armies to blame for their losses, even if it had only been a portion of the enemy force.
From the Battle of Tunis to the end of the First Punic War the Roman armies refused to engage the Carthaginians on any terrain that was suitable for elephants, and they finally defeated a Carthaginian force at the Battle of Panormus, where the Carthaginian elephantry panicked as a result of attacks by skirmishers with javelins. The panicked elephantry smashed back through the Carthaginian line and the Romans carried the day.
The last major battle with elephantry between Rome and Carthage was the Battle of Zama in the Second Punic War. Hannibal Barca led a large force of Carthaginian mercenaries, phalanxes, allied cavalry, and elephantry against Scipio Africanus's legions. Scipio was prepared for the elephantry and created special lanes inside his formation to funnel the elephants to points where the javelin throwers could hit their exposed flanks. Once again the elephants panicked and threw the Carthaginian forces in to disarray, leading to another Roman victory.
Terror and Inspiration
Elephantry was a weapon of terror in the minds of it's enemies, but their actual capability on the field of battle was negligible. It was a psychological weapon that could change the way an enemy general prepared. If the enemy general saw them as a nuisance that could be dealt with they we ineffective, but an army that was unprepared for them could be shattered before even taking the field.
As a tool to inspire they served very well. In the east and west they were the mounts of kings and generals. They led triumphant parades and marches in to enemy cities. Elephants are majestic creatures, but they serve better for their utility than for their military capability.