Absolutely interesting facts about ONAM festival and History 

Onam is also celebrated by the worldwide Malayali diaspora. Celebrations are notable in the United Arab Emirates, Singapore, United Kingdom, New Zealand, Australia, United States, and in France (Paris, Marseille)

Absolutely interesting facts about ONAM festival and History 

Onam (Malayalam: ഓണം, romanized: Ōṇaṁ) is an annual harvest festival celebrated in the Indian state of Kerala. A major annual event for Keralites, it is the official festival of the state and includes a spectrum of cultural events.

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Absolutely interesting facts about ONAM festival and History

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Drawing from Hindu mythology, Onam commemorates King Mahabali. Within the textual tradition (prim. Mahabharata), Mahabali is noted to be an Asura, who found liberation at the feet of Vishnu through charity and religious rectitude.

However, there are other interpretations of the same myth cycle. One version, situated within the Bali tradition, celebrates him as a lower-caste Dravidian who challenged Brahminic hegemony.

In the state-sanctioned celebrations, Mahabali is portrayed as a cultural hero: a just and benevolent ruler, he chose to even give up his rule/life for protecting his subjects and was allowed by Vamana to return back once a year.

The festival probably has ancient origins and it became intricately linked with Hindu legends at some later date. The earliest known reference is found in Maturaikkāñci – a Sangam poem – which mentions Onam being celebrated in Madurai temples. Since then, multiple temple inscriptions record celebrations of Onam.

The date is based on the Panchangam which falls on the 22nd Nakshatra Thiruvonam in the month Chingam of Malayalam calendar, which in the Gregorian calendar falls between August–September. In a neo-liberal India, the festival has been increasingly re-positioned as a tourist event. It has also been subject to multiple political appropriations

— Ritty A.

Lukose notes that a festival that has been culturally inclusive within the "secular lexicon" of Hinduism is being increasingly turned into an event of exclusivism by Hindu Nationalists.

Onam is an ancient festival of Kerala that celebrates rice harvest. The significance of the festival is in Indian mythology, of which two are more common.

Literature and epigraphical evidence suggest that Onam has a long religious context and history in Kerala and neighbouring parts of South India: The earliest known reference to Onam is found in Maturaikkāñci – a Sangam era Tamil poem.

It mentions Onam being celebrated in Madurai temples when games and duels were held in temple premises, oblations were sent to the temples, people wore new clothes and feasted. The 9th-century Pathikas and Pallads by Periyazharwar describes Onam celebrations and offerings to Vishnu, mentions feasts and community events.

An 11th-century inscription in the Thrikkakara Temple (Kochi) dedicated to Vamana – an avatar of Vishnu – mentions a series of offerings made by a votary over two days prior and on Thiru Onam.

A 12th-century inscription in the Tiruvalla Temple, one of the largest Hindu temples in Kerala dedicated to Vishnu, mentions Onam and states a donation was made to the temple as the Onam festival offering. Uddanda Sastrikal, a Sanskrit poet from the court of the Zamorin, has written about a festival called śrāvaṇa.

It is presumed that this is none other than Onam as śrāvaṇa is the Sanskrit name of the nakshatra Thiruvonam.

चोकुयन्ते पृथुकततयश्चापतादिन्य उच्चैः सर्वानार्यःपतिभिरनिशम् लम्भयन्त्यर्थकामान्। बभ्रम्यन्ते सकलपुरुषैर्वल्लभाभ्यः प्रदातुम् चित्रम् वस्त्रम् श्रावणकुतुकम् वर्तते केरळेषु॥

'Gangs of lads, playing their bows hoot loudly again and again; All women make their husbands provide wealth and pleasure; All men are wandering hither and thither to present beautiful garments to their women.

The festivity of 'Sravana' takes place in Kerala. A 16th-century European memoir describes Onam. It mentions among other things that Onam is always celebrated in September, the Malayali people adorn their homes with flowers and daub them over with cow's dung believing its auspicious association with goddess Lakshmi.

According to Kurup, Onam has been historically a Hindu temple-based community festival celebrated over a period of many days.