A war elephant is an elephant that was trained for battle. Elephants were guided by people. The main use of the elephant was in shock tactics to charge against the enemy, trample them, and break their lines. They were first used in India, but their use spread to other regions. Pyrrhus of Epirus used many of them, and so did the armies of Carthage. Hannibal crossed the Alps with a number of war elephants and marched against Rome. 