Thrissur Pooram is one of the most popular temple festivals of the South Indian state Kerala. It is held at the Vadakkunnathan Temple in Thrissur town every year on the 'Pooram' day of the Malayalam Calendar month of 'Medam'. 'Pooram' day is the day when the moon rises with the Pooram star

Thrissur Pooram was the brain child of Raja Rama Varma or famously known as Sakthan Thampuran, the Maharaja of Cochin (1790–1805). Before the start of Thrissur Pooram, the largest temple festival in Kerala was the one-day festival held at Aarattupuzha knows as Arattupuzha Pooram. Temples in and around City of Thrissur were regular participants. One day because of incessant rains they were late for the Arattupuzha Pooram and were denied access to the Pooram procession. Felt embarrassed by the denial, the temples went to the Sakthan Thampuran and told their story.

The Eastern group called as Paramekkavu Bagavathi Temple, consisting in addition to Paramekkavu temple, Karamukku, Chembukavu, Choorakottukavu and Panamukkamppilly. The Pooram was to be centered around the Vadakkunnathan Temple, with all these temples sending their Poorams (the whole procession), to pay obeisance to the Shiva, the presiding deity. The Thampuran is believed to have chalked out the program and the main events of the Thrissur Pooram festival.

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