See the description of the origin of bengali language for a related topic.
At the dawn of literary history, the vaidik Indians probably lived only in the west, as reflected by later memory: sarasvatIdRSadvatyordevanadyoryadantaram | taM devanirmitaM dezaM brahmAvartaM pracakSate || Rgveda doesn't mention the praYAga of gaGgA and yamunA. The vaGga tribes of the eastern region are first mentioned in aitareya AraNyaka (‘vaYAMsi vaGgAbagadhAshcerapAdAH’, probably around 800–500 BC) as un-aryan tribes. Similarly, in the aitareya brAhmaNa (probably around 1200–800 BC), the puNDra tribe (along with andhra, shavara, pulinda and mutiba tribes) is called dasyu, and is again clearly foreign to the writer. In the mahAbhArata (around the beginning of the christian era), the coastal tribes of Bengal are called mleccha, in the bhAgavata purANa, the sumha tribe (along with kirAta, hUNa, andhra, pulinda, pukkasa, AbhIra, yavana and khasa tribes) is equated with sin. BaudhAyana dharmasUtra says that (in one form: avanto(a)GgamagadhAH surASTrAH dakSiNApathAH | upAvRt sindhusauvIrA ete saGkIRNayonaYaH || ... AraTTAn kAraskarAn puNDrAn sauvIrAn vaGgakaliGgAn | pranUnAM iti ca gatvA yajeta sarvapRSThaYA vA ||) the puNDra and vaGga tribes (along with AraTTa, sauvIra and kaliGga tribes) are ‘saGkIRNa yonaYaH’ and outside the aryan domain ... even, a visit to these places required penances to be purified. The jaina text AYAraGga sUtra describes the insults, atrocities and hardships faced by mahAvIra (5–6th cent BC) in rADh.a country and says that the food there was inedible. Similarly, the buddhist AryamaJjushrImUlakalpagrantha says that the language spoken in GauD.a, puNDra, samataTa and harikela was asura. This shows that the aryan way of life had probably not been adopted in this region till at least slightly before the christian era.
On the contrary, the description of raghu's conquests in the rAmAYaNa, karNa's and bhIma's conquests in mahAbhArata, and mahAvIra's travels in AYAraGga sUtra show enough evidence of contacts between the region of Bengal and the aryan culture. In fact, the vaGgas (along with agGas and magadhas) seem to marry into the ruling families of ayodhYA in the rAmAYaNa. In the vAyu and matsya purANas, as well as in the mahabhArata, vaGga/bhaGga, punDra and sumha (along with aGga and kaliGga) were born of the blind holy man dIrghatapas/dIrghatamas (‘austere penance’ or ‘deep blindness’) and sudeSNA (‘good gift’), the wife of vali, the king of asuras. These indicate efforts at incorporating these people into the class sruture of the aryans. devala even allows a pilgrimage here: aGga vaGga kaliGgeSu saurASTra magadheSu ca | tIrthayAtrAM vinA gacchan punaH saMskAramarhati ||)
Slowly, however, we find the class structure of the aryans penetrating into bengal. The concept of the aryan country went as far east as the range of the black deer (bhAllavIrA: pazcAt sindhu vidhAraNI sUryasyodaYAnaM puraH | yAvat kRSNobhidhAvati tAvadvai brahmavarcasam ||) manu also includes them in AryAvartta (A samudrA vai pUrvAdAttu samudrAttu pazcimAt | taYorevAntaraM giryorAryAvarttaM vidurbudhAH || kRSNasArastu carati mRgo yatra svabhAvataH | sa jJeYo yajJIYo dezo mlecchadezastataH paraH || etAn dviJataYo dezAn saMzreYaran prayatnataH |) and classifies puNDra (along with draviDa, shaka, cIna and other foreign races) as vrAtya (or fallen) ksatriyas. mahAbhArata describes vaGga and puNdra as being ksatriyas. The jaina prajJapanA also calls vaGga and lADh.a as aryans. Interestingly the pAli vinaYapTaka places bengal outside AryAvartta, thought the later saMskRta version includes puNDra in it. A number of places in Bengal (like the bank of karatoYA in puNDra and the end of bhAgirathi in sumha) are classified as tIrtha in the mahAbhArata. In the description of arjuna's travel to the tIrtha's in Bengal are references to brahmins in those regions. vAtsAYana in his kAmasUtra in the 3rd or 4th century AD describes brahmins in Bengal. vAyu and matsyapurANas, as well as the mahAbhArata, describes vaGgas, sumhas and puNDras (as well as shavara, pulinda and kirAtas) as ksatriyas.
However, the exact form of the caste system extant in Bengal and East India today is quite distinct from that prevalent elsewhere. Moreover, the hindus of this region may have been non-vegetarians for a long time. Most of the hindu religious writing from this region actually date to the much later period of the Senas, and tradition claims that by then brahmins in Bengal had lost their knowledge and purity. For a description of one set of traditional stories of origin of modern brahmins in bengal, see the traditions page.
For some contemporary accounts of the people of different regions of early Bengal, look at the general account of people of early Bengal.
Up to history of Bengal