There are various theories, which suggest that they might have had a foreign origin but there are no concrete proofs for this theory. Another theory is that an ancient ruler of Kerela, Cheraman Perumal, invited a section of people, called Chekons, to his kingdom from Ezhathu Nadu (Sri Lanka) - hence the name Ezhava. Still another assumption states that their name, Thiyyas, is derived from Theevy, a corruption of the Sanskrit dwipa (island).

The word 'Ezhava' was probably mentioned for the first time in the 9th century. It appears in the Tariaspally inscription of the Emperor Sthanu Ravi and later in the Tanjavur inscription of Rajaraja Chola. In the latter it was used as the name of a community. The Sangam classics, like the Silappadhikaram and Manimekalai, do not contain any such term but they mention 'Uzhavars' (cultivators) and the phonetic closeness between the two words (Ezhava and Uzhava) is obvious. A possible inference is that the castes of South India had already come into existence a couple of centuries before these inscriptions as a result of the influx during the pre-Christian era of Aryan Brahmins. But their impact then was not as great as Buddhism was the predominant religion. Kerela was first ruled by the Chera dynasty and the Cheras were Villavas or Ezhavas. When, eventually, the Brahmins got the upper hand the social structure changed but the Ezhavas refused to submit to them and paid for it dearly.