The Sena period saw the growth of brahminism in Bengal, and, to a large extent defined the particular brand of eastern or Bengali hinduism. Except in certain corners of bÃkuD.A and puruliYA, there is little sign of Jainism during this period. The different sects of Buddhism are present only as an extremely weak force in the religious atmosphere of this time; except in so far as their tAntrika practices merged into hindu tAntrika practices.
The kings of this period gave large number of land grants to brahmins, and these brahmins are identified with full descriptions of their gotra, pravara, veda, caraNa, and shAkhA affiliations: the gotras sAvarNa (bhRgu-cyavana-ApnuvAna-aurva-jAmadagni pravara), vatsa (bhArgava-cyavana-ApnuvAna-aurvya-jAmadagnya pravara), vAtsya, bhardvAja (bharadvAja-AGgirasa-vArhaspatya pravara), kaushika (vishvAmitra-bandhula-kaushika pravara); and the shAkhAs yajurvedIYa kAnvashAkhA (vAjasaneya caraNa), sAmavedIYa kauThuma shAkhA, and to a lesser extent, RgvedIYa AshvalAYana shAkhA, atharvavedIYa paippalAda shAkhA, seem to be repeatedly mentioned. The different occassions on which these land grants were given were many and varied: yajJas like kanakatulApuruSa, aindrI mahAshAnti, hemAshvamahAdAna, hemAshvarathadAna; festivities during candragrahANa, sUryagrahaNa, utthAnadvAdasha, uttarAYaNasaGkrAnti; or just to get what the shivapurANa promises those that give grants of land.
Similarly, this period saw the writing of most of the holy texts of hinduism by the likes of bhaTTa bhavadeva, jImUtavAhana, aniruddha bhaTTa, vallAla sena, lakSmaNa sena, and halAYudha. And the main events in a brahmins life: garbhAdhAna, puMsavana, sImantonnaYana, shoSyantIhoma, jAtakarma, niSkramaNa, nAmakaraNa, pauSTikakarma, annaprAshana, mUrddhAbhighrANa, cuD.AkaraNa, upanaYana, sAvitracaru homa, samAvarttana, vivAha, and gRhapravesha all seem to be observed with lots of rituals. And, yet, halAYudha laments at the same time that the vedic tradition is not as strong in Bengal as in other parts of India; and many of the vedic brahmins seem to come from madhyadesha recently before this period. This is probably echoed much later in the traditional stories of origin of bengali brahmins, written much later.
This rise of the vedic hinduism did not come at the expense of pauranic hinduism either. The stories of the various incarnations of viSNu, including the stories of defeat of vali, the gift giving king of daityas who defeated indra, the love stories of kRSNa, stories of narasiMha and parashurAma, appear in various forms; as do other stories like that of sUryya suppressing vindhya by agastya, candra being a descendant of atri, ardhanArIshvara shiva being the same as shambhu, dhUrjaTi, and maheshvara, and kArtikeYa and ganesha being his sons. A large number of religious occasions are also mentioned: utthAnadvAdashI, sukharAtri vrata, shatrutthAna, kAmamahotsava, holAka, pASANa caturdashI, dyuta pratipada, kojAgara pUrNimA, bhrAtR dvitIYA, AkAsha pradIpa, dIpAnvitA, janmASTamI, ashokASTamI, akSaYa tRtIYA, agastyArghya, mAghI saptamI etc. The use of durvAtRNa with water sprinkled on it as part of giving gifts is also mentioned.
The different sects of hinduism were not really distinct: the same person worshipped various deities equally. However, viSNu in his various forms seems most prominent in this period.
Though the occasional influence of mahAyAna Buddhism on standing viSNu idols continues, and one also finds viSNu sitting on garuD.a, the main idols in this period are the lakSmInArAYaNa form. lakSmI sitting on the left thigh of nArAYaNa is similar to umA-maheshvara idols, and probably came from south India along with the senas. The worship was accompanied by singing and dancing by the bArarAmAs.
Of the incarnations, varAha and narasiMha predominate; the exact number of incarnations had not yet settled down to ten. We also find pradyumneshvara and kAmadeva, the latter from north bengal in the tribhaGga pose, with a bow made of sugarcane, smiling wearing a flower garland.
The conception of rAdhA accompanying kRSNa probably originated in this period, or just slightly later. The stories, however, were immensely popular and the names involved show clear evolution into bengali: kRSNa-kAhNa-kAnu/kAnAi, rAdhikA-rAhI-rAi, kaMsa-kAMsa, nanda-nAnda, abhimanyu-ahivaNNu/ahimaNNu-AihaNa/Aimana-AYAna etc.
Even though the senas continuously invoked sadAshiva, shambhu, dhurjaTi and ardhanArIshvara, the concept of either the tAntrika or Agama shiva-shakti is not visible in these invocations. The Agama conceptions however were common in the preceding Pala period, and likely continued on in this period; the tAntrika concepts probably started slightly later, though we do find mention of mahAnIla sarasvatI and durgottarA right in this period.
One finds various shiva idols in the forms of ishAna, umA-maheshvara, ten (as described in matsyapurANa) or twelve handed dancing shiva holding vINA, snake hood, and cymbals, and sadAshiva; the last two show definite southern influence. Rare examples of gaNapati and kArtikeYa, again of southern style, are also found.
There are idols of what should have been bhuvaneshvarI and mahiSasuramarddinI, yet which are called various forms of caNDI; maybe the meaning of this word was broader. A few cAmuNDA forms have also been found.
It can be argued that sun worship was also prominent in this period, and the shAkadvIpI brahmins probably expanded in influence. sUrya idols in the form of mArtaNDa bhairava have been found as have sUrya between USA and pratyUSA with charioteer aruNa; the latter resembling viSNu with lakSmI, sarasvatI, and garUD.a.
manasA, hArItI, SaSThI, and a few dikpAlas have also been found. The concept of kAlI in this period had probably not yet reached the modern conception. kArttika and the concept of poor-man shiva however do go back to this period. gaGgA worship is also probably present in this period.
The kings of this period were not very sympathetic to the buddhists, and their influence declined rapidly; though a few viharas continued, a few buddhist idols were around, a few scholars like abhaYAkaragupta lived in these times, and a few texts were written in this period. They were often described as pASaNDa-vaitaNDika nAstika, and vallAla sena described himself as an incarnation of nArAYaNa to destroy them. However, lakSmaNasena was probably more tolerant of the buddhists as is evident by his support of buddhist scholar puruSottamadeva.
Of course, the reverse was also true: the buddhists denigrated the hindu gods and goddesses as mAra. Though actual buddhist idols that depict confrontation with Hinduism is rare in India, the texts do describe shiva under the feet of dashabhujAmArIcI, both shiva and gaurI subdued under the feet of trailokyavijaYa, indra holding the umbrella over aparAjitA, indrANI denigrated by paramshva, indra asking favours off ubhaYavarAhAnanAmArIcI, indra under the feet of aSTabhujAmArIcI, paramashva, and prasannatArA, gaNesha under the feet of aparAjitA, parNashavarI, and mahApratisarA, brahmA under the feet of sambara, and harihariharivAhanosdbhava riding on viSNu.
On the other hand, at the popular level, buddhist gods and goddesses often got identified with the hindu ones; and they often crossed pantheons. Thus sarasvatI and vighnanATaka appear among the Buddhist deities, and carcikA and mahAkAla appear in both pantheons. yogAsana viSNu, lokeshvara viSNu, and dhyAnI shiva are probably examples of buddhist influence on hinduism. The identity of tArA, kAlI, durgA, vedamAtA, umA, and padmAvatI is asserted, and vashiSTha is supposed to learn worship of tArA in china. Even in the buddhist viharas like nAlanda, the hindu deities like shiva, viSNu, pArvatI, gaNesha, and manasA started being worshipped.
The common people probably understood little of the buddhist tAntrik practices, and a lot of it degenerated into mere sexual practices. Other than that, hinduism was slowly overcoming buddhism. Furthermore with hinduism having accepting Buddha (respected for being steady in face of carnal temptation and for his kindness to sacrificial animals that lead him to oppose the vedas: jaYadeva sings — nindasi yajJavidherahaha zrutijAtam | sadaYahRdaYadarzitapazughAtam | kezavadhRtabudhazarIra jaYajagadIzahare) as an incarnation of viSNu long back, it was becoming increasingly difficult to distinguish the practices of Buddhism and Hinduism.
The last influence of the buddhists in Bengal was destroyed with the coming of the Turkish conquerors: they destroyed the vihAras of nAlanda, vikramapurI, and odantapurI, killed the buddhists ther, and burnt their books. A few scholars managed to escape with few books and idols to Tibet, Nepal, Kamarup, Orissa, Arakan, Perupagan, or even farther; the scholars of th eastern vihAras like somapura and jagaddala soon followed suit. In the 11th century, zrIdazavalagarbha put a pillar in somapura, that was almost its last moment of glory: karuNAzrImizra burnt to death when vaGgAla soldiers burnt it at the end of 11th or beginning of 12th century. It was, however, somewhat restored by vipulazrImitra. Isolated buddhist scholars continued to exist in Bengal till at least the 15th century.
Islam started spreading in this period. The period is marked by the conquest of Bengal by the Turkish muslims.
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