This section is from the book "Some Contributions Of South India To Indian Culture", by S. Krishnaswami Aiyangar. Also available from Amazon: Some Contributions of South India to Indian Culture.
Coming to inscriptions there are no South Indian inscriptions, as far as is known at present, anterior to the Christian era excepting copies of the Asoka edicts that have been found in two localities, one in the North-Eastern corner of Mysore and the other in the South-Western corner of Hyderabad. There are a few cave-inscriptions in Brahmi character which may be referable to the first century B. C. or even somewhat earlier, but they await interpretation. Lastly there is just one Satavahana inscription in Talgunda in the state of Mysore. Beyond these, inscriptions that throw light upon the history of South India are to our knowledge up to the present, non-existent. We are therefore driven necessarily to a body of literature referable to the century on either side of the Christian era most of them, and which contain embedded in them glimpses of an earlier time. But turning to the northern inscriptions, the inscriptions of Asoka give us some definite knowledge of the political condition even of the remote south, and provide the earliest reliable information on the political condition of South India. Such of Asoka's edicts as do mention these Southern kingdoms mention them as outside the pale of the empire of the great Buddhist ruler liable only to be influenced by the emperor regarding the teaching of "the law of piety." The Chola, the Pandya, Keralaputra and Satiyaputra are mentioned as among "those nations and princes that are his neighbours," and therefore outside of his empire. Coming down to the next century the Hathigumpha inscription of the Kalinga King, Kharavela refers to the arrival of a tribute of jewels and elephants from the Pandya King to the Kalinga ruler thereby confirming, what is inferable from the word kalingam used in Tamil for cloth of a particular kind, that there was trade connection with the country of Kalinga. Even these in-scriptional sources do not advance our knowledge of South India very much; but they do give us to understand that there was a certain degree of communication and a certain amount of knowledge of each other between the two parts of the country. Asoka's edicts themselves make it clear that his empire stopped short of South India, and such communication as did exist was of the peaceful neighbourly kind without giving us any hint of any warlike effort either on his own part or on that of his predecessors. What is wanted in detail in these edicts is supplied to us in Tamil Literature to which we shall now turn.
1 Already known to Brahmana literature: Ait. Br. vii, 14 and Jaimini Up. Br. ii, 640.