The sena rulers of bengal are descendants of a brahmin (brahmakSatra) family of karNATa, and are descendants of vIrasena (called a general of the cholas) of the mythical candra or lunar dynasty (see the mythic geneologies page), and were called of vaidya caste by the later genealogical texts, and kAYastha or else in yet later writings. sena was not an uncommon name among karNATa jaina teachers, and vallAla was a common name amongst the hoYsAlas, but their ultimate origin is not known. His son sAmantasena came to bengal probably during the conquest of vikramAditya VI (aGga, vaGga, kaliGga, gauD.a, magadha, nepAla in 1121 and 1124), or an underling of his (kaliGga, vaGga, gurjara, mAlava in 1122–23) or someshvara III and his son soma (vaGga, kaliGga, magadha, nepAla, andhra, gauD.a, drAviD.a, paramArarAja bhoja, kalacurIrAja karNa in 1127–38), though some of his ancestors are said to have established themselves in gauD.a for a very long time. His son hemantasena established a small kingdom under the pAla king rAmapAla or mahIpAla II, and married yashodevI.
His son parameshvara paramabhaTTAraka mahArAjAdhirAja paramamAheshvara vijaYasena arirAja vRSabhaGkara (ruled c. 1096–1159), also called sukhasena, married vilAsadevI, daughter of the shUra dynasty. We know of a raNashUra in South Bengal during rAjendracola's conquests, and a lakSmIshUra ruler of apAra mandAra (current western hooghly) under rAmapAla is also known. A shUra king AdishUra appears in traditional stories of bengal as having brought in high brAhmins from kanauj to Bengal (he has been variously identified with jaYanta mentioned in the rAjataraGgiNI as being ruler of bengal during the rule of devAditya or jaYApID.a, grandson of lalitAditya of the Aditya dynasty; vIrasena; a son of a mAdhava sena; or husband of candramukhI, daughter of candraketu of kAnyakubja identified with jaYaditya). The same tradition actually gives shUrasena=AdishUra 900–951, bhUshUra 952–970, kSatishUra 970–981, dharAdharashUra 981–994, varendrashUra along with pradyumnashUra 994–1012, anushUra 1012–1030, candrashUra 1030–1048 whose daughter was married by vijaYasena, who ruled from 1048–1066. The difference of 50–100 years between this and the previous date is typical of the uncertainty of the chronology of this period. One must also mention that the entire shUra dynasty tradition has no support from historiography; though nyAYakaNikA by vAcaSpatimizra (c. samvat 898, i.e. 841 AD) of mithilA mentions AdishUra, and he may have settled brAhmaNa families from kolAJca village.
vijayasena might have started from vIrabhUma and conquered gauD.a (actually only varendrI under madanapAla), kAmarUpa (could be vaidyadeva, rAYArideva, or his grandson shrIvallabhadeva), kaliGga, koTATavI king vIraguNa, kaushambI king dvorapavardhana (or could have been the govardhana defeated by jAtavarmA), kaliGga king rAghava, second son of anantavarmaNa coD.agaGga (1156–1170), and mithila king nAnyadeva (c. 1097–1147) of the sena dynasty in bihar. His conquest was probably helped by the defeat of many small bengali kingdoms under Aca who ruled under the karNATas.
The new rule did not bring about administrative discontinuity, by and large previous practice continued. We do find new administrative units like pATaka, caturaka, and AvRtti; and old bhuktis were redrawn: puNDravardhana was enlarged, vardhamAna was reduced, and kaGkagrAma was formed. The sAmantas and amAtyas continued, but the queen, explictly named, was now a part of the council, as was the priest (purohita or mahApurohita). The amAtyas now include important personages called mahAmudrAdhikRta (head of finance?) and mahAsarvAdhikRta (main administrator?); and the different divisions got heads like mahAdharmAdhyakSa (justice), haTTapati (taxation), and mahApilupati, mahAgaNastha, and mavyUhapati (armed forces). The description of the heads (adhyakSa) working with clerks (karaNa) under them, of ambassador (dUta) with spies (gUDh.apuruSa), ministers (mantrapAla), and others appointed by the adhyakSas (adhyakSa pracArokta) points to a system described in the adhyakSapracAra chapter of the classic arthashAstra by kauTilya.
vijaYasena's son paramamAheshvara ballAlasena arirAja niHshaGkara (his teacher was gopAlabhaTTa; his guru was aniruddha; ruled c. 1159–1179) conquered gauD.a probably under govindapAla. He married rAmadevI, daughter of calukya king jagadekamalla II. A number of traditional stories of the establishment of the bengali caste system and origin of brahmins refer to him; and many sayings refer to his library. He may have destroyed the rule of govindapAla, and won over magadha, maybe by 1168. He is said to have divided his kingdom into rADh.a, bArendra, bAgaD.I (gaD.avetA in medinipur), vaGga and mithilA. He was, in addition, a poet himself.
His son gauD.eshvara paramavaiSNava lakSmaNasena, whose minister was halAYudha, ruled c. 1179–1206 (In mithilA, there is a calendar era called lakSmaNa saMvat which starts somewhere between 1079 and 1129, close to 1119. This may have been counted from what was thought to have been his birth. The Bengali valAlI or paragaNAti san may count from the end of lakSmaNasena's rule: such an era was common once), and expanded the sena dominion at least to gauD.a, kaliGga and kAmarUpa, probably also kAshI under the gAhaD.vAla king jaYacandra (successor of vijaYacandra), varANasI and praYaga. He may also have defeated a cedI and a mleccha king. However, even in 1192, buddhagaYa was probably under the gAhaD.avAlas. His kingdom was originally in vijaYapUra or nudiYA, lakSmaNAvati is named after him. In addition to being a poet, he surrounded himself with great poets like dhoYI, sharaNa, jaYadeva, govarddhana, and umApatidhara.
Turkish general Muhammad Bakhtiyar Khilji, without direct orders from Qutbuddin of Delhi (or Muhammad Ghori), attacked and defeated gAhaD.avAla in Bihar. He, however, did not want to disturb the hindu power in mithilA (another karNATaki branch), harishacandra, son of jaYacandra in kanauja or the hindu rulers in rohtas and the region around the sona river. jaYacandra was defeated by sAhabuddIna ghorI in 1194. In 1199, bakhtiyAr attacked and destroyed hisAr-i-bihAr (bihar fort; in reality odaNDapur buddhist vihAra), killed its inhabitants, looted wealth and burnt a lot of manuscripts. In 1200, he attacked Bihar again (by this time vikramashIlA vihar is also described as having been destroyed) and conquered magadha. In 1201 (or 1204), he defeated lakSmaNasena in nadiYA (with only 18 soldiers according to tradition --- they entered the city as horse traders): only he himself managed to escape and set up capital in lakSmaNAvatI, but that too fell to the Turks. However, It was only in 1255 that mughisuddin ujbek circulated coinage celebrating conquest of nadia. Even in 1260, descendants of lakSmaNasena were ruling from vikramapura in east bengal: his sons arirAja vRSabhAGkashaGkara gauD.eshvara yavanAmbaYapralaYakAlarudra vishvarUpasena (c. 1206–1225) and arirAja asahyashaGkara gauD.eshvara yavanAmbaYapralaYakAlarudra keshavasena senakulakamalavikAsabhAskara (c. 1225–1230; though his existence has been doubted) defended vaGga well. giyAsuddIn balban (1211–26), mAlika saifuddIna (1231–33), ijuddIn balban (1258) tried to conquer vaGga, but failed. Tradition however has it that it was lakSmaNa sena II (1123–1203) son of madhusena (1121–1123) son of lakSmaNa sena (1101–1121) who was defeated by bakhtiYar khilji: this is not supported by other evidence. A few more sena kings are mentioned in Abula fajala's Ain-i-AkbarI and rAjAvalI, but except for mAdhavasena, shUrasena=suryasena (son of visvarUpasena?), parameshvara paramasaugata paramamahArAjAdhirAja gauD.eshvara madhusena (in 1289?) and puruSottamasena (son of vishvarUpasena?), it is not clear that they were independent.
There are also evidence of small kings like candrasena, and a kingdom in pIThI (devasena of this place was under madanapAla in 1157) where there were buddhasena in about 1235 and his son jaYasena in around 1285. Tibetan tradition also mentions lavasena, kAshasena, maNitasena, and rAthikasena as independent kings; and lavaNasena, buddhasena, haritasena, and pratItasena under the Turks.
And, finally, tradition has it that the small kingdoms of suketa, keosthala, kaSTaoYAra, maNDI etc. in punjab trace their royal lineages from kings of gauD.a; and the kings use sena as their last names; and we know that magadha was under ashokacalla in 1270.
In 1196, in purvakhAtikA (sundaravana region), mahArAjAdhirAja shrIma dommanapAla, son of paramamaheshvara mahAmANDalika declared independence. raNavaGkamalla harikAladeva (1204–1220) declared independence in paTTikera in the tripurA region. Towards the end of the 12th century, madhumathanadeva or madhusUdanadeva, son of puruSottamadeva declared independence east of meghnA. His son vAsudeva was followed by the most powerful king of this dynasty: dAmodaradeva (1231–1243). Before 1283, vikramapura had become the capital of his son parameshvara paramabhaTTAraka mahArAjAdhirAja arirAjadanujamAdhava dasharathadeva devANvaYakamalavikAsabhAskara (danauja mAdhava; though tradition also links him to the rAYas of candradvIpa) who might also have taken gauD.a from the Turks. After him we still find vIradharadeva, and nargIrvANaH kharavANaH -> gokuladeva or goGunadeva -> nArAYaNadeva -> ripurAja gopIgovinda keshavadeva who maybe the gauD.agovinda, ruler of shrIhaTTa, who, according to tradition, was defeated, along with bhUdeva nRpati of sAtagÃo, by shAh jAlAla according to tradition in 1257 -> ISANadeva, but whether they are related is not clear. In any case, till the end of the 13th century, east bengal was probably under hindu rule. Similarly, in muGgera region, kRSNagupta and his son saGgrAmagupta declared independence.