Onam (Malayalam) is the state festival of Kerala celebrated by all people irrespective of religion though the story behind it surrounds the Hindu mythology of Kerala, India.[1] The festival commemorates the Vamana avatar of Vishnu. It falls during the month of Chingam (August–September) and lasts for ten days. The festival is marked by various festivities, including intricate flower carpets, elaborate banquet lunches, snake boat races, Onappottan, Kaazhchakkula in Guruvayoor, Puli Kali, Kaikottikkali etc. On Onam day people also conduct special prayers in temples.

Significance

Onam is an ancient festival which still survives in modern times. Kerala's rice harvest festival and the Festival of Rain Flowers, which fall on the Malayalam month of Chingam, celebrates the Asura King Mahabali's annual visit from Patala (the underworld). Onam is unique since Mahabali has been revered by the people of Kerala since prehistory.
According to the legend, Kerala witnessed its golden era during the reign of King Mahabali. The Brahma-Vaivarta Puranam explains that Lord Vishnu wanted to curb the pride of Indra; and therefore positioned Mahabali in great power.[2]
The Bhagavata Purana reads 'He [Vishnu] will take the kingdom away from Purandara [Lord Indra] and give it to Bali Maharaja.'[3]
The subjects under Mahabali's reign were happy and prosperous and the king was highly regarded, so much so that even the gods under.