Non co-operative federalism?

Kannada speaking Kalabhras from Shrawanabelagola, who also spoke Sauraseni-prakrit, subdued the early Chozha, Chera, Pandyan kingdoms; and ruled  Tamil Nadu for 3 centuries.

Pallavas subdued Kalabhras in north Tamil Nadu. 

Pandyan Kadunkone, the fierce regent, with his navy from east, subdued Kalabhras, in south Tamil Nadu. 

Muth-tiraiyars - syndicate that collected tax from 3 kings - were subdued by Wijayalaya, in a medieval Chozha revival. 

Insciiptions are scanty, of the Kalabhra era. 

Most common name found in inscriptions, that document Kalabhra presence is, Ravi. 

- as held by south indian historians