In ancient days Vaisyas of Lunar Race lived at Santhyapuri of Shambu Islands in Naganadu up to Kali year 203 (2896BC). The historians say Vaisya's emigrations in Kanjeepuram of Thondaimandalam was in Kali year 204 (2897 BC) and the nestle in naganadu was more than 4867 years. In Kali Year 2311 (790 BC) Prathapa Rasa Thondaimandalam became new emperor of Thondaimandalam. They stayed there for a very long time, but being troubled by heavy levy, they left the country on Kali Year 2312 (689 BC) and settled in Chola country. Manuneedhee Cholan the Emperor of Chola mandalam welcomed Vaisyas with royal respects and he entitled them as "Mahugada-Vaisyar" and asked them to residents at South, East and West street of Kaveripoom pattinam (Poompugar). Since the Chola king knows about the trade and other aspects of Vaisyas he bestow them three privileges as follow: -

(1) Placing the crown on the head of the new ruler at the time of coronation.
(2) They were allowed to use flags with the figure of a lion on them and
(3) To use golden vessels (Thanga- kalasam) in the roof of there houses.

The lion illustration of lion and Golden Vessel (Thanga-kalasam) are royal symbols.

(1) Crowning the Sovereign of Choler's.
(2) Having the Lion flag there own.
(3) To keep the Thanga - Kalasam in the roof of there house.

Poovandhi Cholan crowned as new king of Chola Mandalam on Kali Year 3775 (774 AD). All the 8,000 Vaisyas families destroyed themselves leaving their 1,502 male children to their spiritual instructor named Admanadhachariar. Admanadhachariar brought up the male children. Later due to the illness of Poovanthi Cholan his son Rajabushana Cholan was focused as the new king. Poovandhi Cholan called Vaisyas for the Sovereign his son but Vaisyas refused to accept his invitation since they are bachelors. The sovereign of new king was delayed due to the privileges gave by Manuneedhee Cholan. After a long converse with Shivacharyas (spiritual instructor) and gurus. He asked Vaisyas to marry the Solia- Vellalar girls. Vaisyas agreed to marry them with a resounding that they would not give their children in marriage to Vellala children. After some protest the Vellala peoples agreed to this. Under the royal patronage, mass marriage was performed. Later Rajabushanan Sovereigns as new king of Chola Mandalam.The last migration of the Vaisyas from Chola Mandalam to Pandya Mandalam is by the outstanding request made by Soundaraja Pandiyan to Rajabushana Cholan. The Pandiyan King had approached the Cholan Prince for some good citizens and  Vaisyas after his country was submerged for sometime due to unprecedented deluge, which had caused colossal obliteration to his people, property and cattle. The Chola Prince being sympathetic and finding the plea reasonable persuaded some Vaisyas merchants to migrate to the neighboring kingdom. But the Vaisyas pointed out they are not agreeable for the community to be separated as they would like to stay united wherever the 

So all the Vaisyas move with Raja-Saundra Pandiyan. They first came to the place Known as OmkaraKudi in the Pandya Dynasty. As promised the Pandya king allotted three lands and temples to the three street Vaisyas as below. 

(1) Ariyalur town & Temple of Phiranmalai. 
(2) Sundarapattinam & its Temple . 
(3) Ilayathtankudi Nagaram & its Temple . 

Vaisyas were also known as ArruValiyenar (East) NaluValiyenr (west) and YeluValiyenar (south) as they lived in kaveri Poom Pattinam.Sine they married a Different (sub divisions) Vellalar Females they divided in to three and shared the temples and towns equally. Due to some cold war all the East and west street Vaisyas left the vicinity and went to Malayala desam. Ilayathtankudi Temple and Nagaram belongs to Yellu Valliyenar (present Nattu Kottai Chettiars or Nagarathars) and the people who settled in this Nagaram came to be called as Nagarathars. Later Eight Sub-Divisions have been maid by Nagarathars in the following years.

Now Nattu Kottai Chettiars or Nagarathars have Nine Divisions these divisions are known as Kovils and an single family (A Couple)is known as Pulli. This Nine Divisions are known as Nagara Kovil. Later nagarathar's spread to nearby villages and reside there as a member of there belonging Kovils. Thus the 96 villages came into existence. The Chettiars then moved nearer to the middle of their settlement from the quite remote off villages, and the number of Nagarathar villages decrease to the present 76 villages