Jalamdhara was one of the Asuras or demon who born out of rage of the Shiva. Jalamdhara attained so much power that he was able to conquer the world. He was the son of Ganga and the sea. There is a story relating the birth of Jalamdhara.
One day all the gods went to the abode of Shiva in Kailasha. They pleased the supreme Lord Shiva with songs and dancing. Shiva was so pleased that he asked them to wish any boon. Indra asked him to be a great warrior like him. Shiva granted the wish and the gods departed. Shiva wondered why Indra asked to be so much powerful and what he will do with such a power.
With this pondering, Shiva`s anger manifested as a black shape that appeared before the God. It asked Shiva to make him look like the God. Shiva did so and then ordered his anger to go to the river Ganges and have her mate with the sea. The anger obeyed Shiva`s order and the union between Ganga and the sea produced a son named Jalamdhara. Brahma comprehended the power of the child and named him Jalamdhara. When Jalamdhara was born, the earth trembled and wept and the universe shook with thunder. He could fly on the winds, float over the oceans and tame even the most ferocious lions. Jalamdhara was Shiva`s instrument to take revenge on the Gods.
Jalamdhara was made the ruler of the kingdom when he grew to manhood. He was married to Vrinda. The kingdom grew powerful and Jalamdhara became as powerful to challenge the Gods. He gathered an army and invaded heaven. The war was dreadful and thousands died. As Jalamdhara had the ability to revive the dead, his army never grew weaker. Finally Vishnu met the demon in a single combat, but even he was weaker than Jalamdhara, he lost the battle. His life was only saved by begging of his consort, Lakshmi. Jalamdhara chased the Devas or gods out from the heaven and he started ruling at their place.
The Gods did not yield so early. They went to Shiva again and asked for his help. Shiva now realized the result of his anger and was ready to do anything to throw away Jalamdhara. He advised the Gods to combine their powers and create one most powerful weapon. The Gods created flames, which burned white hot, to which Shiva added the power of his third eye and Vishnu contributed his divine anger. Shiva consolidated the fire under his foot, and coalesced it into a discus of flame. The weapon was so bright and dazzling that Brahma`s beard turned red and Shiva had to hold it under his armpit to hide its glare.
While the Gods were plotting their vengeance, Jalamdhara was besieging Mount Kailasha. His goal was to win Shiva`s wife Parvati, whom he lusted. Parvati was so afraid that she escaped and hid herself in the form of a lotus flower while her attendants transformed themselves into bees and swarmed around her to protect her. While Jalamdhara was after Parvati Vishnu went to his wife Vrinda in the guise of the demon. When Vrinda came to know that she had slept with someone else other than her husband she cursed her seducer and died out of grief.
Jalamdhara was furious when he came to know about his wife`s death and he wanted to meet the army of Gods to crush them at once forever. Another dreaded battle started between Shiva and the demons. Shiva pulled forth the flaming discus and it flew to severe the head of Jalamdhara. Thus Shiva`s own creation turned his enemy.
Jalamdhara lost his head but promptly grew another one. Shiva grew desperate and beheaded the demon again and again but each time he developed a new head. Shiva grew desperate and called on the goddesses for help. The goddesses came as outrageous ogresses and drank the blood of Jalamdhara as it flowed on the ground. Soon Jalamdhara became weak and could not continue the battle any more and was finally defeated. Thus Jalamdhara was destroyed and gods were able to regain their home.
