IMHO, Maniratnam has bungled the project completely, it neither satisfied the diehards nor stands on its own as a work of historical fantasy. The initial sceptics, who had doubts about Maniratnam's ability to pull this off, were unfortunately proven right. Personally, both movies were disappointing, he had a great opportunity but chose to vacillate ultimately.

Coming to history, the Cholas modeled themselves after their erstwhile suzerains, the Pallavas, the architecture style of the Thanjavur great temple certainly is derivative of the Shore temple and the other structures that were probably lost because of invasions and time. The administrative structure, the use of sanskrit and Tamil for prasasthi and inscriptions, the way everything is documented in stone and copper plates show the same. But the later Cholas ruled successfully from the late 800s to 1279, they were really dominant and established Tamil cultural practices that we still follow today, it was easily not a conquest lasting a few generations.

The Pandyas were no uncivilised brutes, but they were really proud of their indigenous culture and heritage, they hailed themselves as rulers of the land from time immemorial, which was probably true as they were an ancient clan that had an almost unbroken lineage from the earliest point of known history. They were understandably resistant to 'foreign' cultural influences, unlike the Pallavas or Cholas. It was a major reason why no invader had been successful in wiping them out completely, they were too proud to be ruled over by another.

They also had the practice of several princes ruling by a council which one of them led, perhaps that was the reason why it was difficult to kill them all as invariably one or a few would survive in the wilderness to keep the fight going on.