In ancient India, there were many wars between families. As it was these families had vast armies and part of the "equipment" if that is the right word are elephant. Height is a great advantage in war and so Elephant were used to great effect. Of course they could trample on, break down walls or defences but most importantly of all, they created a presence. A dominant, invincible fear of god look. But elephants can be cut down and many have been. So the idea of armour to protect them would seem logical. In truth it didn't work, heavy and cumbersome, it just added to the weight already there. But impressive it looks..
