Durga Puja, also known as Durgotsava or Sharodotsav, is an annual festival originating in the Indian subcontinent which reveres and pays homage to the Hindu goddess Durga, and is also celebrated because of Durga's victory over Mahishasura. It is particularly celebrated in the Eastern Indian states of Bengal, Assam ,Odisha and by Hindus in Bangladesh. The festival is observed in the Indian calendar in the month of Ashvin, which corresponds to September–October in the Gregorian calendar. Durga Puja is a ten-day festival, of which the last five are of the most significance. The puja is performed in homes and public, the latter featuring a temporary stage and structural decorations. The festival is also marked by scripture recitations, performance arts, revelry, gift-giving, family visits, feasting, and public processions called a melā. Durga Puja is an important festival in the Shaktism tradition of Hinduism. Durga Puja in Kolkata has been inscribed on the intangible cultural heritage list of UNESCO in December 2021.

Navaratri is an annual Hindu festival observed in honor of the goddess Durga, an aspect of Adi Parashakti, the supreme goddess. It spans over nine nights, first in the month of Chaitra, and again in the month of Ashvin (September–October). It is observed for different reasons and celebrated differently in various parts of the Hindu Indian cultural sphere. Theoretically, there are four seasonal Navaratri. However, in practice, it is the post-monsoon autumn festival called Sharada Navaratri. There are 2 Gupta Navaratris or "Secret Navaratris" as well, one starting on the Shukla Paksha Pratipada of the Magha Month and another starting in the Shukla Paksha Pratipada of Jyestha Month.