Kali Puja is celebrated to diminish the ego and all negative tendencies that hinder spiritual progress and material prosperity. Performed on the night of Kartik Amavasya, which falls in October/November, Kali Puja is an intense invocation to the fearsome goddess. The main purpose of the puja is to seek the help of the goddess in destroying evil - both in the outside world and within us.
The legend goes that long ago the demons, Sumbha and Nishumbha, disturbed the peace of Indra, the king of gods, and his empire (heaven). After extensive and endless battles, the gods lost all hope and the demons became stronger.
The gods took refuge in the Himalayas, the holy mountains, the home of Lord Shiva and Parvati. The shaken gods sought protection from Mahamaya Durga, the goddess of Shakti. Kali was born from Durga's forehead as Kal Bhoi Nashini, created to save heaven and earth from the growing cruelty of the demons. Along with Dakini and Jogini, her two escorts, she set on her way to end the war and kill the devils.