[10][11] The Barbaras, Kiratas, Paradas, Saka-Greeks, Indo-Greeks, Pulindas, Scythians,[12] Kushans,[13] Kinnaras,[14] Tusharas,[15] Nishadas,[16] Türks, Mongols, Romans, Balochs[17] and Arabs were also mlecchas.
[22] Asko Parpola has proposed a Dravidian derivation for "Meluḫḫa", as mel-akam ("high country", a possible etymological relationship and reference to Balochistan from where originated the Indus Valley Civilization.
Parasher continued, "The best experts of the sacrificial art were undoubtedly the various families of the Brahmins who, placed in a hierarchy within the Indo-Aryan social system, became the upholders of pure and best speech".
Though they were considered a marginal group, the area characterize as the mleccha-desa (the natural border that separated their lands from that of the Aryans) was never permanent.
Parasher noted that the only consistent areas dubbed as mleccha desa were those regions inhabited by primitive tribes who for long periods of time did not come under the sway of the Vedic, Buddhist or Jain influence.
Early Vedic literature focused on defining the area of habitation of the Aryas for this land was considered pure; yet there is no actual reference to the mleccha country or behavior.
The Achaemenid Persian Empire, which ruled over the Indus River Valley during this time (522–486 BC) was not designated as mleccha, perhaps because they did not interfere with the Brahminical way of life.
[35] Later Vedic literature speaks of the western Anava tribes as mlecchas and occupying northern Punjab, Sindh and eastern Rajputana.
As such there were intricate rules in place to define purity from impurity, laws of behavior, as well as rituals and customs, in an effort to educate the members of the Brahmanical system.
[18][42] In the Mahabharata, some Mleccha warriors are described as having heads completely shaved or half-shaved or covered with matted locks, as being impure in habits, and of crooked faces and noses[43] They are dwellers of hills and denizens of mountain-caves.
Mlecchas were born of the cow (belonging to Vasishtha), of fierce eyes, accomplished in smiting looking like messengers of Death, and all conversant with the deceptive powers of the Asuras.
[44] Swami Parmeshwaranand states the mleccha tribe was born from the tail of the celestial cow Nandini, kept by Vashishta for sacrificial purposes when there was a fight between Vishvamitra and Vasistha.
The Mahabharata gives the following information regarding them: The term is not attested in the Vedas, but occurs for the first time in the late Vedic text the Shatapatha Brahmana.
[47] The Baudhayana sutras define a mleccha as someone who eats beef or indulges in self-contradictory statements or is devoid of righteousness and purity of conduct.
[50] According to the Gwalior inscription of his descendant Mihira Bhoja, the Gurjara Pratihara King Nagabhata I repulsed a mleccha invasion.