What was the main reason for the Mahabharata war?
There was enmity between Kauravas and Pandavas and all the elders of Kuru dynasty knew that. However, after the marriage of the Pandavas with Draupadi, Shri Krishna and others impressed upon Dhritarashtra to give Pandavas share in the Kingdom. Hence, Pandavas were given their land with Indraprastha as their capital. Pandavas developed their kingdom depending upon their own strength. Hence, thereafter there were no quarrels between Kauravas and Pandavas. However, after attending to the Rajasuya Yagna, Duryodhana was overwhelmed with jealousy and impressed upon Dhritarashtra to invite Yudhisthira to game of dice. Duryodhana knew well that though Yudhisthira was fond of game of dice, he was not an expert in that game. Then, Dhritarashtra send invitation to Yudhisthira for game of dice, through Vidura. The following is the conversation between Yudhisthira and Vidura . [y] dyūte kṣattaḥ kalaho vidyate; naḥ kaś vai dyūtaṃ rocayed yudhyamānaḥ kiṃ vā bhavān manyate yuktarū...