The greatest Indian empire was the Mauryan empire when the Indian culture, values and power were at it's zenith. The Mauryans were Buddhist. This was despised by the Brahmin citizens. They felt insecure that Buddhism believes in a person's capabilities to attain nirvana by ones own karma instead of the caste he is born in. So to maintain their caste based superiorty the Hindu Brahman general of the Mauryan emperor whom the emperor has trusted so much, murdered the emperor and formed the Sunga dynasty. The name of this traitor was Pusyamitra Sunga. Not surprisigly his agenda was to maintain the caste superiority of his caste-men and he went about destroying the grand and happy Indian civilization built by the Buddhist emperorts. After successfully destroying Buddhist stupas, Buddhist knowlege and murdering Buddhist monks who were mostly non-Brahmin Indians, this traitor brought the grand Mauryan empire to it's demise. Foreign invaders like the Greeks, Afghans, Persians and Turks took over India. Check out further information about this traitor at the following link: http://en.wikipedia.org/wiki/Pusyamitra_Sunga
Nobody teaches us this part of the Indian history. Nobody teaches us how Hemu a vaishya king who defeated Humayon (Akbar's father) and briefly ended the Mughal empire was cheated by Brahmins and Kshatrias since a vaishya cannot be made a king. The alignment of these people with the Mughals cost Hemu his life and put India on track for Mughal rule. Sh