The Mahabharata is the great battle of Kurukshetra. It took place between two families - the Pandavas and the Kauravas for the sovereignty of Northern India and the throne of Hastinapur. The Pandavas were the 5 sons of Pandu and the Kauravas were their cousins, the 100 sons of King Dhritashtra, Pandu's blind younger brother who was now king as Pandu was no more. After Dhritashtra, the throne rightly belonged to Yudhisthir, the oldest son of Pandu. But of course, the Kauravas would have none of that.

Duryodhan, the oldest of the Kauravas, was an extremely wicked man and had cheated the Pandavas out of their kingdom in a game of dice. He had also tried to strip Draupadi, who was the common wife of the Pandavas, in front of all at the palace after the Pandavas had lost the game. And were it not for the timely intervention of Lord Krishna, he would have succeeded in this dastardly deed. Therefore it was on the advice of the Lord that the Pandavas were ready to battle for their rights.

The Pandavas were also first cousins of Lord Krishna as their mother was the sister of his father. But as Lord Krishna did not wish to be impartial, he offered himself to one party and his entire army, of a hundred million soldiers, to the other. Arjuna of the Pandavas, chose the Lord himself and the Kauravas were only too pleased to have his whole army, little realising that the blessings of God would definitely be stronger than an entire army.

 Lord Krishna participated as a friend and advisor and rode Arjuna's chariot into battle. He had pledged that he would not take part in the actual combat. A pledge that he found almost difficult to keep when he found his cousins losing. 

His main role in the battle as Arjuna's charioteer was to inspire and encourage Arjuna when the latter wanted to give it all up. He did not want to fight his kinsmen and revered teachers who had taught him all he knew, just for the sake of a kingdom. And this is the moment when Lord Krishna recited the Bhagvad Gita, the epic poem that forms the basis of Hinduism. Through this poem he encouraged Arjuna to pick up his weapon and fight for justice as that is his 'dharma' or sacred duty.

Arjuna said that he did not want to be responsible for killing so many people. And Lord Krishna replied that the soul is immortal and cannot be destroyed so it is not really possible to kill anyone. He then revealed his 'viraat roop' or real divine form to Arjuna. When Arjuna realised that he had the lord himself (the incarnation of Lord Vishnu) on his side he was filled with a deep sense of awe and was greatly encouraged to carry on. 

The battle proved long and hard and carried on for 18 days. The Pandavas knew that it was impossible to win as long as their great 'guru' or teacher Dronacharya continued to battle. This great 'brahmin' was highly skilled in the art of warfare and could not be defeated. The Pandavas would have to come up with a plan.