''The belief that Krishna's policy & statesmanship was the really effective force behind Yudhisthere's greatness, pervades the epic. But who were these nations that resented so strongly the attempt of Yudhisthere & Krishna to impose an empire on them?
It is a significant fact that the Southern and Western peoples went almost solid for Duryodhana in this quarrel—Madra, the Deccan, Avanti, Sindhu Sauvira, Gandhara, in one long line from southern Mysore to northern Candahar; the Aryan colonies in the yet half civilised regions of the Lower valley of the Ganges espoused the same cause.
The Eastern nations, heirs of the Ixvaacou imperial idea, went equally solid for Yudhisthere. The Central peoples, repositories of the great Kuru Panchala tradition as well as the Yadavas, who were really a Central nation though they had trekked to the West, were divided.
Now this distribution is exactly what we should have expected. The nations which are most averse to enter into an imperial system & cherish most their separate existence are those which are outside the centre of civilisation, hardy, warlike, only partially refined; and their aversion is still more emphatic when they have never or only for a short time been part of an empire...
That the nations of the East & South and the Aryan colonies in Bengal should oppose the imperialist policy of Krishna & throw in their lot with Duryodhana is therefore no more than we should expect. On the other hand nations at the very heart of civilisation, who have formed at one time or another dominant parts of an empire fall easily into imperial schemes, but personal rivalry, the desire of each to be the centre of empire, divides them and brings them into conflict not any difference of political temperament. For nations have very tenacious memories and are always attempting to renew the great ages of their past. In the Eastern peoples the imperialistic idea was very strong and having failed to assert a new empire of their own under Jarasundha, they seem to have turned with one consent to Yudhisthere as the man who could alone realise their ideal.''
Sri Aurobindo - Notes on Mahabharata