Onam is an important festival of Kerala. It usually comes in the month of August or September. The people of Kerala eagerly look forward to this festival. It is celebrated all over Kerala with great pomp and show.
Most famous and oft quoted mythology is connected with Vamana the fifth incarnation of Maha Vishnu. As per this, Mahabali, an emperor who ruled the then Kerala (it is not the present Kerala) in an exemplary manner and as a model ruler, started attracting the attention of even Devas (who also had become under their control). They thought that if he continued the rule like this the position of Devendra (the King of Devas) will be in trouble. They brought this into the notice of Maha Vishnu, who promised to find a solution for this. He decided to visit Mahabali in the guise of a brahmin boy named Vamana. Mahabali was always ready to give anything he owned to anybody on request and he was a stickler to his words. Knowing this character, Vamana requested for three footage of land, which he would measure with his foot and take. Mahabali immediately agreed to this demand since it was nothing to him, since he had a very large kingdom itself under his command. Then Vamana took his original form (Thrivikraman â€“ Maha Vishnu) and measured the whole of fourteen worlds with his two steps and requested Mahabali to provide space for the third step. Mahabali, having understood who Vamana was, stood on knees in front of him and requested to place his third foot on his head. Vamana did so and pushed Mahabali into Pathalam, thereby bringing an end to his rule. Before going down, Mahabali requested Vamana to allow him to visit Kerala once in a year to see his people. This was agreed upon.
Thus Mahabali is believed to be visiting Kerala on Thiruvonam day (in the month Chingam), which is being celebrated as Onam by every Malayalee.
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