Legend foretells two common folklores from where it is believed Kojagori Lakshmi Pujo started. According to the first folklore it appears that Valit, a misfortune but a religious and pious Brahmin from Magadha left home one full moon night tired of his wife Mahachandi’s errant for being poor and lack of wealth and prosperity. Valit while wandering in the woods confronted 3 Nagkanyas or daughters of a serpent worshipping Goddess Lakshmi by performing a Vrath or fast to seek blessings of Lakshmi and offered Valit to play a game of dice with them in order to keep awake. Goddess Lakshmi, who was on vigil, observed Valit closely and was impressed with his honestly and religious gestures and blessed him with wealth and fortune by helping him win the game. Valit returned home with tons of gold. Hence it is believed that performing fast on this auspicious night is beneficial for gaining wealth and prosperity and fortune blessed and offered by Goddess Lakshmi in return, and therefore women play game of dice till wee hours in the night to keep awake.
The second folklore narrates the story of a king in Bengal who bought an unsold idol of Goddess Alakshmi (God of poverty) from his craftsmen in order to help them earn their livelihood. He put this idol in his temple next to the idol of Goddess Lakhsmi. As Lakshmi & Alskhsmi cannot coexist Goddess Lakhsmi silently left and misfortune prevailed in the kingdom driving away wealth and prosperity. The hapless king prayed to Dharma for help who advised that his wife perform a Vrath or fast and worship Goddess MahaLakshmi on Kojagori Purnima to ward off Alakshmi. Wide awake till wee hours of the night playing dice, the king’s wife performed the fast and worshipped, offered prayers. Impressed by her gesture & devotion, MahaLakshmi blessed the kingdom with wealth. It seems that the idol of Alakshmi melted away thus reinstating prosperity and wealth in the kingdom.