P. Kalyanasundaram Pillai was born in Kumbakonam on 25 September 1912 to Ponniahpillai. Inspired by the philosophies of Gandhi since childhood he participated in some freedom struggles for our country. In May 1930, he was imprisoned for six months in Tiruchirappalli Jail along with Ramasamy for pasting posters with slogans about the tyranny of the British. He participated in the Civil Disobedience movement in 1932 and was arrested and sentenced to six months. He was arrested again in the same year under the Press Emergency Act and kept in Tiruchirappalli Central Jail; he was released on 6th January 1933.
In 1941, he started his own business to use the proceeds to help the poor and create a sense of freedom among the people. P. Kalyanasundaram Pillai was recognized as a freedom fighter and was awarded the Central Martyrs' Pension Certificate in 1980 by former Chief Minister M. Bhaktavatsalam and land for farming in Mannargudi. From 1 August 1980 onwards until his death, he would receive 300 rupees per month and after his death, his wife Sivakamasundari would receive 200 rupees. His son Sampath said that the land was suitable for cultivation and sold it later. V. Nadesan and Kaakaji Ramaswamy were in the same cell with Kalyanasundaram Pillai when he was in Tiruchirappalli Central Jail. The government of India, in 1988, in celebration of the 41st anniversary of Indian Independence awarded him a Tamra Patra.