Jambavant is the king of bears in the Indian epic Ramayana (though he is also described as a monkey in other scriptures), immortal to all but his father Vishnu.
Several times he is mentioned as Kapishreshtha (foremost among the monkeys) and other epithets generally given to the Vanaras. He is also known as Riksharaj (King of the Rikshas). Rikshas are described as something like Vanaras but in later versions of Ramayana Rikshas are described as bears.
Jambavant was present at the churning of the Ocean and is supposed to have circled Vamana seven times when he was acquiring the three worlds from Mahabali. He received a boon from Lord Rama that he would be handsome, have the strength of ten million lions, and live a long life.
In the Ramayana, Jambavant was created by Brahma, as a king of the Himalayas to assist Rama in his struggle against Ravana. It is Jambavant who makes Hanuman realize his immense power and encourages him to fly across the ocean to search for Sita in Lanka.