The sarpasattra as per the itihAsa was the gory sacrifice of janamejaya pArIkshita done to avenge the death of his father parIkShit by the sarpas. The itihAsa states that the interaction between the pANDus, yadus and the sarpa-s was a long-standing and complicated one. arjuna first fathers a son irAvAn, through the sarpa princes ulUpI, the daughter of kauravya, the son of dhR^itarAshTra airAvata. kR^iShNa devakIputra defeats a sarpa king kali~nga according to the harivaMsha on the yamuna. Then arjuna the pANDu and kR^ishna the yadu attack khANDavaprastha the kingdom of the takShaka the king of the nAga-s and defeat him to seize his land, with the vedic deities from indra to rudra fighting on the side of the sarpas. The pANDus build their new capital there. In the great war the half-sarpa son of arjuna comes to fight on his side and is killed, whereas takShaka tries to aid karNa in killing arjuna. After the war the sarpa-s avenge themselves on parIkShit, called the grandson of arjuna, and kill him. Finally, this is avenged by janamejaya in his sarpa-sattra where he massacres the sarpas. The sarpa-s are saved from complete extinction by deva indra who sends the brAhmin AstIka to end the rite of janamejaya. In addition this battle, the bhArgava utanka fights takShaka in the quest for the earrings of the queen.
In the veda, the sarpa-sattra is mentioned in the pa~nchaviMsha brAhmaNa (25.15), the baudhAyana shrauta sUtra (17.18) and the baudhAyana gR^ihya sUtra (3.10). It is said that the kings and princes of the sarpas performed it in order to gain firm grip over over the worlds or for obtaining poison. The sacrificer is asked to perform the sattra if he wishes similarly to gain a grip over the worlds. The sAmavedic brAhmaNa briefly describes the rite as having two atirAtras in the beginning and end of it, and two agniShTomas in the middle of it. The only unpaired day in the annual sattra is the viShuvAn day. On the other days a 10 versed recitation is used but on the viShuvAn day the 12 versed chant with the sarpa sAmans are deployed. These are the AraNyageyagAnaMs 2.a.1-10.
This leads us to another mysterious aspect of the sarpa-s found in the vaidika tradition, namely the sarpa-sUkta-s attributed to the arbuda and his mother kadru, the queen of the sarpa-s (sarpa-rAj~nI). These sUkta are: 1) RV 10.94 attributed to arbuda the son of kadru directed to the soma-pounding stones to prepare soma for indra. The sarpa arbuda is the foe-destroying snake probably related to the snake-poison arbudi weapon of atharvan tradition. In the RV, indra slew him with a snow-shower or an icicle. 2) RV 10.189 attributed the sarpa-rAj~nI kadru the mother of the serpentine tArkShya-s and the sun. It dappled cow in the sUkta might be a metaphor for the dappled sarparAj~nI. Who might this sarparAj~nI associated with the sun be? The aitareya brAhmaNa, explaining the deployment of this sUkta during in the ritual snake-like creeping of the R^itkvik-s to altar, states that she is the earth (also repeated in the shatapatha brAhmaNa) because the earth is queen of what creeps. It states that the earth was barren but when she saw this sUkta, the dappled color entered entered and thus all plants and birds entered her. In the famous sarpa-balI incantation from the yajuSh tradition we hear that the sarpa-s are seen in the realms of light (the rochana; mentioned in above sUkta) and the rays of the sun (sUryasya rashmi). The same kadru is also offered an oblation with the incantation of kadrave nAgamAtre svAhA | in the sarpa-bali and the bodhAyana ritual to rudra. Thus, from the context of the sUkta this serpentine deity appears to be associated with the earth receiving the solar rays and becoming fertile. Thus, the sarpa-s as R^iShi-s and officiants has a wider presence in the veda.
Most remarkable aspect of the vedic rite done by the sarpa-s is the consistently preserved list of officiants seen in both the sAmavedic and baudhAyana texts. The brahmA priest is mentioned as dhR^itarAShTra airAvata, while the brAhmanAchChamsin is takShaka, and the adhvaryu is janamejaya. The baudhAyana texts mention uparIti tArkShya (the half brother of the khaga, ariShTanemI tArkShya). The interesting feature is that the vedic sarpa sattra is done by the sarpa-s in the veda and is not the killing of the sarpa-s as in the itihAsa. It again has several of the circum-pANDu characters of the itihAsa except the pANDus themselves. This again highlights the big question we had asked earlier: Why are the vedic texts silent about the pANDus? The answer to this question is indeed central to some major historical transitions in India.
mAnasa-taraMgiNI 