Nahusha was a king who had performed 100 Ashwamedha Yagnas but he is infamous for this pride and arrogance as he made saints his palanquin bearers. He had become so powerful and was chosen to take the place of Indra by Devas. Indra was then hiding in Manasarovar as result of a curse. Once he received the title of Devendra, Nahusha became arrogant. He started to harass women in Devlok. He even did not spare Indrani – the wife of Indra.
Devas and saints tolerated Nahusha as without a leader the Asuras (demons) would attack and defeat them.
Fed up with Nahusha, Indrani approached Brihaspati for help. When Nahusha came to know about this he started to create troubles for Rishis. Indrani then approached Indra in Manasarovar. Indra gave her an idea to overcome the womanizer.
Indrani then returned to Devlok and when Nahusha approached her; she said that she will become his wife if he arrives in her palace on a palanquin carried by Maharishis.
Immediately Nahusha ordered for a new palanquin and asked four Maharishis including Sage Agastya to carry him on the palanquin to the palace of Indrani
The Maharishis carried Nahusha on the palanquin to the palace but they were walking slowly. This angered Nahusha. He started to abuse and hit the Rishis with whip.
Sage Agastya could no longer tolerate the arrogance of Nahusha and cursed him that he become a snake.
Nahusha became a huge snake and took refuge in the Himalayas . Pandavas during their exile reached the cave in which the huge snake was hiding. It attacked Bhima, the second of the Pandavas.
Yudhisthira immediately came to know that this was no ordinary snake. He then asked the snake about its origin. On narrating his story, Nahusha was relieved of the curse.