The history of the temple is mentioned in the Brahmanda Purana, one of the eighteen famed Hindu scriptures. Per Hindu legend, Tulasi once did penance to attain closeness to Vishnu. Vishnu responded that his consort Lakshmi would appear under Tulasi's lap in Tiruvinnagaram.
Tulasi appeared in the place where the temple is located. This is mentioned in the 53rd verse of Nammazhwaar in Thiruviruththam. Markandeya Maharishi worshipped Vishnu and desired that Lakshmi should appear as his daughter and Vishnu should become his son-in-law. Once Markandeya was on a holy trip and after reaching Thiruvinnagaram, he felt it was the right place to get his desire fulfilled. Markandeya started a severe penance for thousand years, seeking Lakshmi's blessings.
Lakshmi appeared as a baby under the already incarnated tulasi plant. Markandeya felt Lakshmi's presence in the form of the baby and realised that part of his desire had been fulfilled.
He took possession of the baby and raised her. When the young girl reached adolescence, on the panguni month of Shravana, Vishnu appeared as an old man and asked for the hand of Markandeya's daughter in marriage.
Markandeya replied, "You are very ripe and old, my daughter is too young and she does not even know how to cook with proper salt contents", to which the old man replied, "If your daughter must cook without salt, then I will still take it as my best food, but I will not leave from here without marrying her".
Markandeya sought Vishnu's help and then realised using his penance that the old man was Vishnu himself. When he opened his eyes, Vishnu appeared in front of him with conch and chakram as in Vaikundam.
Markandeya offered his daughter's hand in marriage. Per the legend, the temple's Neyvethiyam (food offering) is always prepared without salt.
Temple elephant
The name Oppiliappan is a result of this legend. There is also a story behind the tank in this temple. Once a King had consummated with a daughter of a saint and hence the saint cursed him to become a bird.
The king lived as a bird and one night when there was a storm, the branch of the tree the bird was sleeping on broke and fell into the water of this tank. The bird regained its original form as the King and since then this is known as the only theerththam that one can do theerth thaadanam even in the night.
Since this tank has such healing power in the day as well as night, it is called "Ahoraathra Pushkarani".The place is called by various names, including "Agasa Nagaram", "Vaikunda Nagaram", "Thiruvinnagar", "Oppiliappan Sannithi" and "Uppiliappan Sannithi".
The presiding deity is also called by various names, including Venkatachalapathy, Thiruvinnagarappan, Oppilaappan, Thanoppillaappan, Uppiliappan and Srinivasan.[8]
View of the temple tank
It is not clear from the inscriptions and records when the temple was initiated, but there are inscriptions from the Medieval Cholas period indicating generous gifts to the temple. There are two inscriptions recorded from the Naganathar Temple in Tirunageswaram.
The epigraph numbered 211 of 1911 on the northern wall of the central shrine indicates gift of gold jewel worked in gems and pearls to the temple from the Chola king Parakesarivarman, alias Rajendra Chola I (1012–44 CE). The second inscription numbered 218 of 1911 on the shrine's southern wall indicates a gift of land to the temple in the 14th year of the Chola king Rajaraja Rajakkesarivarman I.
The tradition in many ancient temples in Tamil Nadu including this one is that the original image of the presiding deity is made of wood and replaced later with stone. There were a lot of additions made to the temple by Govinda Dikshitar, the minister of successive Nayak rulers, Achuthappa Nayak (1560–1614) and Raghunatha Nayak (1600–34).
The temple is maintained and administered by the Hindu Religious and Endowment Board of the Government of Tamil Nadu.