The history of Pongal can be traced back to the Sangam Age, ie, 200 B.C. to 300 A.D. Pongal is an ancient festival of the Tamils and it is not known when exactly the Tamils began celebrating the festival, but some historians identify it with the Thai Un and Thai Niradal, believed to have been celebrated during the Sangam Age.

Pongal, a traditional Tamilian food item that has found a place in the menu of Indian restaurants across the world, is perhaps the only dish to have lent its name to a festival. As part of the festivities, maidens of the Sangam era observed penance during the Tamil month of Margazhi (December-January). Throughout the month, they avoided milk and milk products. They would not oil their hair and refrained from using harsh words while speaking. The women had their ceremonial baths early in the morning.

They worshiped the image of Goddess Katyayani, which would be carved out of sand. They ended their penance on the first day of the month of Thai (January-February). This penance was to bring abundant rains and agricultural prosperity for the country.

Thai Niradal was a major festival during the reign of the Pallavas (4th to 8th Century A.D.). Andal's Tiruppavai and Manickavachakar's Tiruvembavai vividly describe the festival. According to an inscription found in the Veeraraghava temple at Tiruvallur, the Chola king Kiluttunga used to gift lands to the temple specially for the Pongal celebrations.

According to Hindu mythology, this is when the day of the gods begins, after a six-month long night. The festival is spread over three days and is the most important and most enthusiastically celebrated harvest festival of South India especially Tamil Nadu. A special puja is performed on the first day of Pongal before the cutting of the paddy. Farmers worship the sun and the earth by anointing their ploughs and sickles with sandal wood paste. It is with these holy tools that the newly-harvested rice is cut.

According to a legend, once Shiva asked his bull, Basava, to go to the earth and ask the mortals to have an oil massage and bath every day and to eat once a month. Inadvertently, Basava announced that everyone should eat daily and have an oil bath once a month. This mistake enraged Shiva who then cursed Basava, banishing him to live on the earth forever. He would have to plough the fields and help people produce more food. Thus the association of this day with cattle.

Each of the three days are marked by different festivities. The first day, Bhogi Pongal, is a day for the family. Surya Pongal, the second day, is dedicated to the worship of Surya, the Sun God. Boiled milk and jaggery is offered to the Sun God. The third day of Pongal, Mattu Pongal, is for worship of the cattle known as Mattu. Cattle are bathed, their horns polished and painted in bright colors, and garlands of flowers placed around their necks. The Pongal that has been offered to the Gods is then given to cattle and birds to eat.