STORY OF DEVI KANNAGI

Kannagi is worshipped as Devi in many areas. She is the epitome of chastity. In Kerela, she is worshipped as Bhadrakali and Attukal Devi.
For Sinhalese Buddhists of Sri Lanka, she is Devi Pattini and Kannaki Amman for the Sri Lankan Tamil Hindus.

Kannagi was the wife of Kovalan, a merchant from Kaveripattinam. He left Kannagi for a dancer Madhavi and spent all his wealth on her. Kovalan, later, returned to Kannagi when he was penniless. The only asset left was a pair of anklets filled with rubies.
@GampaSD @RajeAiyer

Both went to Madurai which was ruled by Pandyan Nedunj Cheliyan 1. Kovalan wanted to sell the anklets and restart his life. However, around the time he set out to sell the anklets, one anklet (out of a pair) was stolen from the queen by someone and it resembled Kannagi’s anklet.

Kovalan was caught and beheaded without any trial. Furious Kannagi reached the court and broke open the anklet to prove Kovalan’s innocence. She flung her anklet and cursed that the entire city would burn. The entire city caught fire and her curse became a reality
@DubeyYash1911

After this, Kannagi on her way to Kodungalloor in Kerala, gave "Darsan" to the natives at Attukal in Thiruvananthapuram. It is said that the Devi finally reached Kodungalloor and settled at Kodungalloor Devi Mandir.

Kannagi is also the main character of the epic Silapathikaram.