Besides these three dynasties, the Sangam era Tamilakam (Tamil homeland) was also divided into various provinces named 'nadu', meaning 'country'.
Sangam literature refers these provinces as "koduntamil mandalam" which were not exactly political or socio-cultural units but linguistic agglomerations like Kongu Nadu, Puzhinadu, Thondai Nadu, Nanjilnadu, Ay Nadu and Venadu.
In Attirampakkam, archaeologists from the Sharma Centre for Heritage Education excavated ancient stone tools which suggests that humanlike population exists in the Tamil Nadu region somewhere around 300,000 ago before homo sapiens arrived from Africa.
In Adichanallur, 24 km (15 mi) from Tirunelveli, archaeologists from the Archaeological Survey of India (ASI) unearthed 169 clay urns containing human skulls, skeletons, bones, husks, grains of rice, charred rice and celts of the Neolithic period, 3,800 years ago.
It is bounded by the Eastern Ghats on the north, by the Nilgiri, the Anamalai Hills, and Kerala on the west, by the Bay of Bengal in the east, by the Gulf of Mannar and the Palk Strait on the southeast, and by the Indian Ocean on the south.
Three dynasties, namely the Chera, Chola and Pandya, ruled the area of present-day Tamil Nadu and Kerala.
The Chera ruled the whole of present-day Kerala and parts of western Tamil Nadu comprising Coimbatore, Dharmapuri, Karur, Salem and Erode districts from the capital of Vanchi Muthur (thought to be modern day Karur).
Between the 3rd and 6th centuries AD, the three Tamil kingdoms were overwhelmed by the Kalabhras.
The period of their rule is sometimes referred to as the "Dark Age" in Tamil history and little is known about it.