Diwali and Kali Pooja
In Bengali tradition Kali Pooja is celebrated on the night of Diwali. Kali is considered as one of the only two pre-Aryan deities other being Lord Shiva. According to a legend, Lord Shiva lay down on the path of goddess Kali, who went on a rampage slaughtering demons. After she stepped unknowingly on Shiva's bare body, she calmed down.