Jalandhar was one of the greatest Warrior ever mentioned in ancient Hindu texts. As per Shiv purana, Jalandhar was the only warrior who defeated both lord Ganesha and Karthik single handedly. Very few know that Jalandhar was responsible for abduction of Sita in Ramayana.
As per purana(shiv), Indra and Brihaspati were going to meet Shiva at Mount kailash. A yogi with matted hair and radiant face blocked their way. This yogi was no other than Shiva himself who had taken the form to test the knowledge of both of them. Indra didn't recognised the yogi. He asked him to move aside but Shiva did not budge. Indra became furious and threatened him with his thunderbolt. Upon this action Indra's arm became paralyzed. Shiva neutralized the thunderbolt. Shiva became angry on the action of indra. His eyes turned red, frightening Indra. The anger caused Shiva's third eye open throwing flames out. This nearly killed Indra. Brihaspati recognised Shiva and prayed him, requesting him to pardon Indra. To avoid Indra, he deflected the fire towards the ocean. Upon meeting with the ocean it is assumed that it took a form of a boy.
The boy cried terribly which caused Bramha to descent from heaven. The ocean told Bramha that he did not know where the boy came from. Bramha then told him that the boy will one day become the Emperor of Asuras. He could only be killed by Shiva and after his death he would return to shiva's third eye.
Jalandhar was exceedingly powerful and is considered to be one of the mightiest Asuras of all time. He married Vrinda, the daughter of Asur Kalanemi. Jalandhar ruled with Justice and nobility. Sage Bhrigu came to meet Jalandhar and narrated him the stories of Hiranyakashipu and Virochana. After hearing this he came to conclusion that Devtas has taken his father's treasure. He sent his messenger Ghasmar to ask Indra to return his father's treasure. Indra refused and the fierce battle between Devtas and Asuras started.
Warriors on both side we're killed. Asuras overpowered Devtas. They asked lord Vishnu for help. Lakshmi asked Vishnu not to kill Jalandhar as he was born out of the ocean and Lakshmi considered him as her brother. After the defeat of Jalandhar, Vishnu asked him to demand any boon he desired. Jalandhar asked Vishnu to make ksheera Sagara his home. He agreed and started living there with Lakshmi.
After this, Jalandhar insults Shiva and the fierce battle started between Shiva and Jalandhar. Jalandhar disguised as Shiva tried to trick Parvati. Parvati recognised him and got very angry. Parvati then went to Vishnu and requested him to trick Vrinda just like Jalandhar tried to trick her.
Vrinda recognizes Vishnu and cursed him that someday someone would abduct his own wife and then enters the fire to immolate herself. After hearing his wife's death, Jalandhar got angry and attacked mount kailash. Jalandhar engaged in battle with Shiva who killed him with his Trishul. After his death his soul returned with Shiva.