Wikipedia
Periyalwar or Periazhwar (3055 BC, a mythology estimate) is one of the twelve azhwar saints of South India, who are known for their affiliation to Vaishnava tradition of Hinduism. Vishnucitta or Periyalwar incarnated on this earth in the 47th year after the beginning of the Kali Era (3102 BC). The verses of azhwars are compiled as Nalayira Divya Prabandham and the 108 temples revered are classified as Divya desam. According to some accounts, Periyazhwar is considered the first in the line of the twelve azhwars, while other accounts place him as the eighth. His original name is Vishnuchittar and he since he is considered the oldest among azhwars, he is called Periazhwar.
Related to his birth, the traditional scriptures mention that Goda Devi or Andal, the daughter of Vishnuchittar incarnated on this earth in the 98th year after the beginning of the Kali Era (3102 BC). As per Hindu legend, Periyazhwar was the foster father of Andal, the only female azhwars.The works of Periyazhwar contributed to the philosophical and theological ideas of Vaishnavism. His contributions are Thirupallandu and Periya Azhwar thirumozhi among the 4000 stanzas in the Nalayira Divya Prabandam.
In South-Indian Vishnu temples, Periyazhwar has images and festivals associated with him. The Garudasevai festival in Srivilliputhur temple, where five Vishnu temples in the region participate, is an event dedicated to him. The verses of Periyazhwar and other azhwars are recited as a part of daily prayers and during festive occasions in most Vishnu temples in South India.