"The Brahmana said, 'In this connection is cited the ancient story, O lady, of the discourse between Karttaviryya and the Ocean. There was a king of the name of Karttaviryya-Arjuna who was endued with a thousand arms. He conquered, with his bow, the Earth, extending to the shores of the ocean. It has been heard by us that, once on a time, as he was walking on the shores of the sea, proud of his might, he showered hundreds of shafts on that vast receptacle of waters. The Ocean, bowing down unto him, said, with joined hands,--Do not, O hero, shoot thy shafts (at me)! Say, what shall I do to thee. With these mighty arrows shot by thee, those creatures which have taken shelter in me are being killed, O tiger among kings. Do thou, O lord, grant them security.'
"Arjuna said, 'If any wielder of the bow exists that is equal to me in battle, and that would stand against me in the field, do thou name him to me!'
"The Ocean said, If thou hast heard, O king, of the great Rishi Jamadagni, his son is competent to duly receive thee as a guest.--Then that king proceeded, filled with great wrath. Arrived at that retreat, he found Rama himself. With his kinsmen he began to do many acts that were hostile to Rama, and caused much trouble to that high-souled hero. Then the energy, which was immeasurable of Rama blazed forth, burning the troops of the foe, O lotus-eyed one. Taking up his battle-axe, Rama suddenly put forth his power, and hacked that thousand-armed hero, like a tree of many branches. Beholding him slain and prostrated on the earth, all his kinsmen, uniting together, and taking up their darts, rushed at Rama, who was then seated, from all sides. Rama also, taking up his bow and quickly ascending on his car, shot showers of arrows and chastised the army of the king. Then, some of the Kshatriyas, afflicted with the terror of Jamadagni's son, entered mountain-fastnesses, like deer afflicted by the lion. Of them that were unable, through fear of Rama, to discharge the duties ordained for their order, the progeny became Vrishalas owing to their inability to find Brahmanas. 1 In this way Dravidas and Abhiras and Pundras, together with the Savaras, became Vrishalas through those men who had Kshatriya duties assigned to them (in consequence of their birth), falling away (from those duties). Then the Kshatriyas that were begotten by
the Brahmanas upon Kshatriya women that had lost their heroic children, were repeatedly destroyed by Jamadagni's son. The slaughter proceeded one and twenty times. At its conclusion a bodiless voice, sweet and proceeding from heaven, and which was heard by all people, spoke to Rama, 'O Rama, O Rama, desist! What met it dost thou see, O son, in thus destroying repeatedly these inferior Kshatriyas?' 1 In this way, O blessed dame, his grandsires, headed by Richika, addressed that high-souled one, saying. 'Do thou desist.' Rama, however, unable to forgive the slaughter of his sire, replied unto those Rishis saying, 'It behoves you not to forbid me.' The Pitris then said, 'O foremost of all victorious men, it behoves thee not to slay these inferior Kshatriyas. It is not proper that thyself, being a Brahmana, should slay these kings.'"
51:1 Kshatriyas always require Brahmanas for assisting them in their acts. These particular Kshatriyas, through fear of Rama, fled to the forests and mountains. They could not, accordingly, find Brahmanas for assisting them. Their children, therefore, fell away from the status of Kshatriyas and became Vrishalas or Sudras.