A king named Anga was descended from Svayuambhuva Manu. Anga married Sunitha, the daughter of Mrityu, and they had a son named Vena. Mrityu was an evil person. From his childhood, Vena associated with this maternal grandfather of his and thus came to acquire evil ways. When Vena became king after Anga, he started to oppress the world. He stopped all yajnas and the prayers to the gods. He insisted that people should pray only to Vena. The sages did their level best to persuade Vena to return to the righteous path, but Vena would not listen.
The sages then killed Vena. Vena had no sons and a kingdom does not flourish in the absence of a king. Therefore, when Vena was dead, the sages started to knead the dead body so that a son might be born. The first being that emerged as a result of this kneading was a dark and dwarfish son. All the evil that was in Vena‘s body entered the body of this son so that there was no more evil left in the dead body.
When the kneading continued, a handsome son was born from Vena‘s right hand. He was born fully grown and held bows, arrows and clubs in his hands when he emerged. His entire body was clad in shining armour. The word prithu means great. Since the son was born after a great deal of effort, he was given the name Prithu.
The sages made arrangements for Prithu‘s coronation. Prithu was a good king who ruled well. But Prithu‘s subjects still did not have the wherewithal to make a living. They asked their king to do something about this. Prithu decided that since the earth was not providing any foodgrains, he would kill the earth. The earth adopted the form of a cow and started to flee. Wherever the earth went, the king followed in hot pursuit.
The earth finally realized that she could not escape by running away. She told Prithu, ―Please do not kill me. Then your subjects will not even have a place to live in. Your object is to find a means of living for your subjects. How will that be accomplished if you kill me? Milk me instead of killing me. The foodgrains that the milking will yield will provide the sustenance for your subjects.‖
Prithu accordingly milked the earth. It is because of this that the earth is known as prithivi. Prithu also levelled out the earth with his bow so that his subjects could live in the plains thus created. The earth prospered during Prithu‘s rule. Poverty, disease and sins were unknown. Everyone was righteous.