A Brief history
The Asian elephant was used in battle as early as 1100 B.C., but it was not until 326 B.C., at the Battle of Hydaspes, that the first European commander encountered elephants in battle. Alexander the Great defeated an army commanded by Poros at Hydaspes, in modern Pundjab, and of the 200 Indian war elephants deployed there Alexander captured 80 animals which he later incorporated into his own army. In the course of his campaigns, Alexander was able to gather as many as 200 elephants in his army. King Pyrrhus of Epirus defeated the Romans at the battle of Heraclea (280 B.C.), on the Gulf of Tarent, primarly because of the 26 Indian elephants in his command.
After the Indian elephant had proven its worth in battle, the Egyptians and Carthaginians deployed African plains elephants in the same role. The animals were tamed and prepared for battle in eastern Sudan and Tunisia. The plains elephant is much larger and heavier than the Indian elephant. Properly armed and armoured, the plains elephant became a formidable enemy for infantry and cavalry. The crew of a Carthaginian war elephant typically consisted of four men, the Numidian Mahout who controlled the animal, and three Carthaginian soldiers in the tower: officer, archer, and infantryman armed with the Sarissa, a lance 5 - 6 m long.
The Numidians used African forest elephants in battle. Many of these animals were captured in the woods of the Atlas mountains. These relatively small animals could not carry a tower, they were ridden by a crew of two or three men. The Mahout controlled the animal, and the other two men were armed with bow and arrows, or javelins.
European military historians have often dismissed war elephants as ineffective and even dangerous, but in fact they were quite useful. They were strong beasts of burden once tamed, and thus they were of great assistance to travelling armies bearing heavy loads. They were also very useful in battle. They could charge at up to 25 kilometres per hour, and they had difficulty stopping once they reached that speed. The stampeding beasts therefore often crushed enemy armies. Elephants were also very difficult to kill, and thus opposing armies were often sent scrambling for safety when they charged. Additionally, war elephants had a frightening presence for armies that had never seen them before. Horses and camels unaccustomed to elephants were similarly spooked, and often ran off in fear. Indian armies did not simply rely on the elephants' physical presence to frighten their opponents into defeat, however. They also used the elephants' enormous size to their advantage by stationing armed soldiers atop the animals. Archers and javelin throwers atop war elephants had a distinct advantage over the army on the ground.
There were disadvantages to the use of elephants in war, however. Although they were difficult to kill, several wounds to an elephant, or the loss of the animal's driver, could cause the elephant to lose control and become dangerous to its own army. Also, with the invention and widespread use of gunpowder in warfare in the 16th century, elephants became easier to kill, and thus their effectiveness decreased.
In 1398, however, Timur was able to defeat the army of the Delhi Sultanate, and its elephants. Although it is difficult to say for sure how Timur got past the elephants, one tale says that after seeing the Delhi Sultanate's 120 war elephants, Timur offered a special prayer to Allah, then attached straw to the backs of the camels in his own army. When the camels got close to the elephants, Timur ignited the straw, thus encouraging the camels to run forward. The flaming camels racing towards them frightened the elephants, who ended up crushing many Indian troops in their haste to retreat.
However he managed to defeat them, Timur was so impressed with their performance in battle that he went to the trouble of obtaining war elephants for himself to use in his upcoming battles against the Mamluks and the Ottomans, both of whom he subsequently defeated.